Hi!
I think whether it's okay to play for stacks here depends on what kind of fish he is. It's hard to say from just the stats of 20 hands, however if you think he is capable of bluffing or that JJ beats most of his hands here go ahead, but it will probably be a high variance play unless he is calling you with trash. You certainly never have to shove JJ here if you aren't comfortable with it.
Also I don't know about just shoving straight away. I would probably make it 18.75 if I chose to raise, but I would like to hear someones opinion on that as well.
As for the move itself, assuming you are talking about re-raising after being squeezed, it can of course be very profitable in the right spots against aggressive opponents who are capable of squeezing.
Anyways those are just my thoughts so I might be completely wrong.