Analyzing limit table sessions

Since I seem to be having a period where I couldn't win with AA if 49 of the remaining 50 cards were A, I thought I would go through and analyze some of my table sessions to see where I can neaten up my game.

I have right around 5,000 hands in my database of limit, spread between .02/.04 and .10/.20, mostly (half) .05/.10 FR. My current BB/100 is 5.38 and I've won 110/261 sessions.

What I'm curious about is that with only one exception, if I do not win one of the first two hands I participate in, I never get above my buy-in, regardless of time spent at the table. If I lose more than roughly 15% of my buy-in, I never break even and usually lose a good bit more. If I get above my buy-in and then go below it, I only recover about 30% of the time.

What statistics should I be looking at to figure out what's going on? It doesn't seem that I play any differently during a winning session and a losing one, not many hands, aggressive with hits, not chasing dead draws but it seems one session my hits hold and the next (or even second table at the same time) every top hand gets drawn out.

So, basically, I want to know what to look for that I'm doing wrong. Should I be comparing aggression, VP, PFR, 3bet% or what? I'm not sure how variance can explain the statistics I'm getting so it must be me.