Breast lumps! Help!

Hey there, I'm not sure what's going on. I'm 16 and I was doing a self examination on my breasts when I found an odd large lump two fingers above my areola. I'm scared that it could be cancer. But I don't think it hits girls my age. I've also been told that it can happen for no reason at all and go away. I'm quite anxious about this. If anyone knows what it might be I would really appreciate it.