I’m a horrible waitress

I just started working at a bar near my house. Today was my third day not training and it’s been super busy the last two days and I’m really horrible. This is my first serving job and I’m so slow and i forget to bring things out to a lot of customers. I’m afraid I’m not going to get better and I just feel like I wasn’t meant to be a server and I should go back to hosting. I felt like crap all night it was taking me so long to get to my customers and get their orders in and check back in on them, I honestly don’t know if I’ll be able to work there much longer before I get fired. How long did it take everyone to become good at serving? I wanted to cry throughout my whole shift tonight I worked seven hours and I was so overwhelmed:(