Whether or not it's cancer, the testicular movement sounds very unusual and I would personally get checked out.

Well, if you masturbate or make love, just before the climax, testicles move kinda up, but no idea, why it is not comfortable, when i masturbate or have sex, they get up, and just later get down . But I have read in somekind of magazine, don't know if it's true, but during sex, if you feel that you gonna blow your load out, the balls move up, and just when youre about to get off, move them down with your fingers, hand, or whatever, i don't know how true it is, never tryed it tho.

I think I'd personally go get myself checked out. Being healthy isn't a bad thing.

thanks for the advice

right before ejaculation it is normal for them to retract - or "get tight" as I call it. However, the pain/discomfort you feel I don't think is normal. That I would get checked out.

Yeah, the tightening/retracting is perfectly normal as a man nears orgasm (though it probably doesn't happen to all men) or as he gets more aroused.

Mangucho - that sounds familiar - yes, it is possible to prolong enjoyment by gently pulling them back away from the body.

Jimbo - the pain/discomfort as they descend does sound like something you should speak to a doctor about.