I checked pre-flop because of all the callers (with likely overcards) and the fact that I was out of position. Usually this is a raise for me (and trust me, I am not a weak player), but I had just read something saying that with four or more callers, you could try just checking jacks from the BB due to the positional disadvantage.

From there, I wanted to get in a check-raise on the flop, not bet it out due to the fact that I could just be building a pot for flush and/or straight draws. However, mwbeirne's raise on the flop made me suspicious that he might already have the nut straight (or at the very least, a very strong hand, two pair or trips, possibly).

I don't think the rest of the hand was worth going into calldown mode, especially with the jack high flush draw (against a likely made hand).