TL;DR: Your bad mood may have made the situation worse, but the personal question was definitely out of line. It's up to you how you handle such situations in the future, whether you choose to escalate or just tell off the employee and leave it at that.
I was very angry and stressed for other reasons.
I've worked retail as my main job for a while, and there's a lot that goes into working well with customers that already come in angry or upset, even if their anger/upset is because of other reasons totally unrelated to their shopping experience. If a customer comes in that is visibly angry, your hands often feel tied, and it immediately throws you off from your 'standard' way of working, which is usually to do things and be cheerful about it. You suddenly feel you can't be as cheerful anymore, because it might upset the customer even more.
First they tried to downplay the problem and make it seem like I was the one who couldn't operate the machine. They told me that I shouldn't press too hard on the knob.
Usually, this isn't the employee trying to downplay the issue. There's a big chance that in 90 percent of the cases just asking/telling customers to try again but not pressing the button so hard works and solves the problem.
As you said in your comment, the machine actually needed some parts replaced before it worked. But even in such cases, an employee is likely to first make sure they really have to do so, by again telling you to press the button with less force. This will save both them and you a lot of time.
It helps to realize that you can always calmly explain that you tried, and ask for an employee to help you out. That doesn't have to be the employee you're currently dealing with: they might be busy and refer you to a colleague, give them that chance.
Then they gave me a very frustrated look, like I was thoroughly disturbing them.
You might have been disturbing them, they might've been doing a task that needed to be done quickly or which isn't put aside easily. While it really is NOT professional to show so, I can't count the times I've been thoroughly annoyed at having to stop doing what I was doing to help someone with an issue.
For example, if I was cleaning, it required taking off gloves, getting your hands wet anyway and drying them off, making sure the cleaning supplies were stashed at a place where no kids could stumble across them and no items were in places (like on the floor) where customers could be bothered by them. Then I'd spend a few seconds to go get a colleague with more information or help the customer, then back to cleaning just to find that the spot or thing I was cleaning had dried up all ugly and I could basically start again with that.
It takes a lot of effort to consciously manage your body language in a way that hides the annoyance of being disturbed at your task, and supermarket jobs are usually filled by people that just see it as a temporary/side job. Usual supermarket employees are 16-year-olds with no training in dealing with customers So this employee might very well have had a bad hold on their body language because of being untrained/unused to doing so. It doesn't make it okay, but maybe knowing this might help you refrain from answering annoyance with more annoyance next time.
I did not say or do anything offensive, just stood there with body language that probably communicated: "You are an employee and I a customer. This is your job. Do it".
That to me sounds like it might completely have thrown me off, especially when I just started working retail. Your body language might've made things worse here. It might make an employee nervous, unsure, and feel like they were doing something very wrong. If they're very young/untrained, they'll be easily flustered and have no clue on how to deal with an upset customer. It might also make them hesitant to refer you to a colleague if your request for help is made while they are really busy.
Again, a good professional should be able to deal with this and not let things bother them so much, but a friendlier and more open attitude that doesn't show your anger as much might get you further next time.
Then the employee started squirting too much orange juice into my bottle until it overflowed. I could not help saying "Ooh come on man". So the employee quickly got another bottle and started filling it to the brim.
Like I said, your body language might've made the employee nervous, which caused the overflow. Your remark of 'Ooh come on man' isn't very specific. The employee probably understood you didn't want a bottle that was sticky from overspilt orange juice on the outside, and started to make up by filling another bottle.
Next time, try to be a bit more specific. You could for example calmly ask them for a wet wipe/towel to clean the outside of the bottle, and tell them that now the bottle is all dirty and you can't take it home like that. Or you can ask them to pour the juice in a clean bottle. That way you avoid the whole 'filling up another bottle and then arguing about wasting the first'.
Then the employee asked me if I was Muslim. This infuriated me, and I told them that it was none of their business, and that I was going to notify their superior.
I really can't see where this question would've come from. It may have been a genuine attempt at having some sort of friendly conversation or relating to you, because the employee noticed you were upset. To me this seems out of the blue and unprofessional though, like it was to you. Telling them that it was none of their business was the right thing to do.
The store manager basically confirmed this: They also thought it was strange for the employee to ask this. The manager may not have said as much when both of you were present to avoid totally embarrassing the employee and further escalating the situation, but from my experience, this usually means the manager is on your side and a good manager will sternly tell their employee to not to go asking such questions again in private.
But if you want to avoid escalating, here was your chance. You had your juice, and you told them it was none of their business. You could've left it at that, taken your bottle of juice, told them the question was inappropriate and turned your back on them, without telling them you'd notify their superior.
What would have been a better way to address this situation in order to avoid having escalated to the store manager?
There are a few things you could've done differently:
- Try as hard as you can to not let your bad mood about other things influence your interaction with the store employee.
- Be clear in what you want from the employee, show patience and understanding. Calmly explain that the machine doesn't work for you, remain calm when told to not press the button as hard and explain that you've tried but it still seems to be not working, and ask for an employee to help you out personally. If you want personal help, ask for it, and be prepared to be referred to a less busy colleague. If you don't want to take the dirty bottle home, ask them to clean the bottle or pour the juice in a clean bottle.
- When confronted with personal questions, firmly state that the answer is none of their business or that you'd rather not answer personal questions, and refrain from including the 'notifying their superior' part. You can always do so if this employee continues to be a problem, even if you're in a good mood.