[nath]

This is always a push and you screwed yourslf by your unwilingness to commit to the hand.

As a short stack, you shouldn't be looking to "get away" from any ace folded to you the button.

As for your other question: With your stack, I'm probably pushing in the last four spots. Earlier, depends on the tightness of the table and my image. The first couple of spots are a unique dilemma in that you're running out of time before the blinds chop at you again, but when you get called you are frequently dominated. My experience lately is not to push A-small up front.