I went to the doctor 5 months ago with a lump in my upper arm you cant see it it's under the skin..he said it was a cyst I didnt think anything more if it until a few days ago I was putting a top on and the top rubbed against it and it hurt and it reminded me that the lump was there. I felt it and it seemed bigger not just that but the area around it was swollen. I kept pressing it and it became really painful and the pain lasted all day. I had shooting pains in my shoulder and the cyst itself. the next day my bf felt it and again after that it really started to hurt. I havent touched it today but still have some shooting pains and pressure type feeling aswell. I'm worrying now that it isnt actually a cyst but something else..I've never had a cyst before can some tell me if it's what they experience?