Limping in with JJ is not a good idea.
If you can remember a specific situation when you had it and share more details we can probably be of more assistance to you.
If not - the next time you get it note the following and let us know:
Buy-in/type of tournament
Blind levels
Your stack size and if possible other stack sizes
Any reads you might have on your opponents
Action in front of you if any
Your position at the table
All of these things impact your action.
I went out in 31st in the
wsop Ladies event several years ago. There was an early position raise and a re-raise in front of me.
I had a short stack and shoved - in retrospect it was a mistake. The re-raise from a good solid player was a strong indicator that I was behind. I was hoping for a race - but with 2 players in front of me I should have waited for a better spot to shove.
I don't think my shove was horrible - but it wasn't great either. I was just too worried about blinding down too low and didn't take enough time to think.