I just saw a guy on Party miniraise out of the BB with aces and two limpers and the SB in the pot already. Crazier things have happened.

And I think that your comment about being up for the session and not wanting to lose it is not so bad. That's probably the way you should always play. Unless you feel pretty comfortable that you're in a good situation, why not just fold. Even if you think you might have a slight edge, plenty of times you won't. If you're iffy about a call, then you're probably not in that great of a spot.