Dealing with anxiety…

Help! About six weeks ago I decided I needed to stop feeling sorry for myself and go get a job. I thought that not only did I need the money but I thought it would be a good start in meeting new people. I thought ‘you never know, I might bond with someone and I could finally end up with a friend/group of friends I could have a laugh with’. Oh, how freaking wrong could I be!? I easily got a job waitressing but, of course, I am much older than most of the other staff working there (38, nearly 39 😭). Age doesn’t usually bother me as I can usually find something to relate to someone else but there is one particular girl (aged 19) who I get the feeling has taken an instant dislike to me. I don’t know this for sure, and I certainly don’t want to go running to my manager to say she keeps rolling her eyes at me or hinting that I’m doing a particular bad job at things (it sounds paranoid at best!) so I’ve made the effort to ignore it, crack on and make the best out of the situation. Anyway, last Friday night the place was so busy, it was boiling hot inside and we were short staffed. I ended up making a mistake with one of the table numbers - I held my hands up, apologised profusely and accepted that I was probably going to have caused a bit of unnecessary stress. This particular was absolutely furious with me (or, so it seemed - she was huffing and puffing at me etc). I then started to feel incredibly nervous about making more mistakes, and, inevitably, I did. I gave the customer a wrong dish, again I apologised and explained that I’d only been there a short time, I was still training and that we were incredibly busy and short staffed. My manager agreed we could offer her meal for free to make up for the mix up but she was absolutely furious with me, she was screaming and shouting at me about how incompetent I was. I ended up bursting into tears, telling my manager I couldn’t do this anymore, and walking out. Later on, my manager messaged me and told me not to be so hard on myself - I’d only been there for six weeks, I’d made very few mistakes in that time and that the shift I’d worked had been out of the ordinarily busy. However, I feel so humiliated and pathetic. I was a woman, in her late 30’s, crying her eyes out in a packed out restaurant, working with a girl nearly half my age who intimates me. I am supposed to be working again tomorrow but I literally feel sick at the thought of going back. If I don’t go back, then I will no longer have money to buy pay my bills. My son is starting his summer holidays and I would really like to be able to take him to a couple of places, like the zoo. But the selfish, terrified part of me feels like I CANNOT go back. I’m so embarrassed that I don’t know what to do! Any advice would be much appreciated!!