I have a bump on the skin of my ball sack (it's not sticking out). It's was quite red (looked like a graze). It was itchy but creme stopped that.

Just wanted to know if this is testicular cancer (I thought the bump has to be on the actual testicle).

Your are correct, the mass is on the testicle itself the the skin of the scrotum. It is not a bad idea for men less than age of say 30 to palpate their testicles looking for masses. Testicular cancer is a young mans cancer. You are just fine.

Testicular cancer only occurs on the actual testicle itself. In early detection, you feel for a a lump in one testis. The testicle should normally feel smooth to the touch.