do i have testicle cancer?

[Rambo A]

i was born with a undescended testicle, my right one was put back into to place with surgery. It's half the size of my left one sense i can remember cuz its always bugged me. About 7 months ago i noticed a small lump in my right testicle sac but not on my testicle. it hasn;t hurt ever. the last two days though i have felt a werid pain off and on and my scrotum feels heavy sometimes. I am going to get it looked at but i just wanted to see if you guys thought it could be cancer or maybe a cyst. i got blood work done for a tattoo and my blood work came back clean i don't know if they could have seen cancer on those tests but i just thought i would ask so if u guys could answer this fast i would really aprreciate it cuz i am scared of dying