Field hockey camp coming up what should I do?

There’s a field hockey camp coming up, but I don’t know if I should go or not. It is three days long, and that’s not a problem, but it’s from 9 am to 3 pm…which is really really long. I can’t get any friends to come with me, and all I have is my sister. I love field hockey, but I don’t want to go alone. Where I live, it’s pretty smart to bring a friend to hockey camp with you, so you have a partner. I’ve been in situations at camps before where everyone had their little group of friends, and they all got split up. They would put us in groups of 6, and the one that was left would be with me, because I’m so shy and don’t have anybody else. Once we get in the group, I try to start a conversation, and they would just ignore me. The person doing this is the coach of a high school (the one I’m going to), so everyone is going to impress her so she knows us before tryouts for the high school’s hockey team. My mom tells me anyone who doesn’t want to do this is just stupid, and my whole family is pressuring me to go. I’m afraid if I go, I won’t meet anyone new, I’ll be left out, I’ll have to eat lunch alone… I’m not the outspoken type. When I was little, I could go anywhere and do anything, but now, a lot of people don’t accept me, because I’m not pretty enough or good enough for them. I’m going to end up going to the same school as them, but I don’t really feel like getting up at 8 every single morning to go play hockey for six hours… Softball is my main sport, I could play that for hours. But field hockey is my main sport in the fall..the summer is all about softball. I love hockey, I just don’t know what I should do. My dad already told me if I don’t go, he’s not letting me stay home, he’s not taking off, and he’s sending me to some daycare. I’m 13. It’s just a lot of pressure..what should I do?