I've been playing casually for about 2 years, mostly SNG's. I say "casually" because while I pay attention while I play, and I read a bit, I'm not studying this game as much as I probably should. Even so, playing mostly $22 games, I'm up about $3000. The last 6 months or so though I've come to a halt. I'm barely keeping even, can't seem to get going, and I'm starting to think that the first $3000 was mostly luck. I still have so much to learn.

OK, here's my question.

I'm in last in a 10-seat SNG with 4 people remaining. $300 blinds and I've got maybe $1200. I get A-10, or A-6 or A-whatever. I go all-in and get called by KQ, or K10 or by 10-9, any two cards between mine. I've lost the last 5 out 6 situations like this. Am I crazy or should I be winning more of these?

I realize that my bigger problem is finding myself short-stacked near the end of the game, but I'm working on that.

Please let me know that whether in this situation I'm playing correctly.