Hi there i would get it checked by a Doctor if symptoms persist Take care ..............Bob
It could be you strained the area, it could be you took some damage (a hit) maybe or it could be an infection. Because it might be an infection, it's a good idea to get it checked out, so nothing 'scary' happens. A urologist will fell the area and have you **** in a cup to rule out infection, that's gonna be it. Maybe you get a scan, but they'll be able to tell you what's up right away for the most part.
Get it checked out, you don't wanna gamble with that sorta thing. Having a doc feel your nuts is weird, but not too weird. After all that doctor does it ALL day every day (being a urologist) and who cares? You'll know what's up in minutes.
I'm no professional, so it could be all kinds of things I don't know and haven't mentioned, I just wanna add.