| First, stop the weight lifts. It's strengthening your hand, yes, but it's can also cause a major upflair in your tendons, leading to tendonitis. And that's a bit of a pickle. Look at doing some better stretching exercises. If you feel a strain during the exercise, you're over-exerting. Jazz Basses tend to have a decent neck, so it shouldn't be the problem. You can also sleep with a wrist brace on at night. That helps. And don't twist your wrist when you play (if you do).
I've got the same bony 'thing' you described and used to pop it, but found out it was pretty terrible for my health, so I stopped immediately.
Hope this helps | 
