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.
Hi there i would get it checked by a Doctor if symptoms persist Take care ..............Bob