A sist or something normal?!

Ok, so four years ago at competitive cheer practice, I hurt my wrist and it was swollen on the bottom. I thought it would be something that ice and elevation could fix. Well now I'm 14 and it's still pretty swollen in the same area. In fact it's gotten a little bigger, and started to hurt really bad when i bend it back and/or put pressure on it. I went to the doctor and the x-rays showed nothing. My mom said I was being to dramatic and it was probably just a blood vein. The doctor made me an appointment with the orthopedic surgeon for tomorrow. My friend Laura's mom is a nurse at Children's Hospital and said it looked like a sist, but she's never seen a sist on the bottom of the wrist. She said they would cut it out and put me in a cast.. Is she right? Or could it be nothing at all. But it does hurt like a mother f*****