On the bright side, you're a winning player over the last 20,000 I would take Jay67s's advice if you haven't already and take a close look at your thirty or forty biggest losing hands. Bad beats? Great. Crying calls? Not so great. Bluffs? Bad. Especially look at your big losses with AKo and see where you could have found a fold. As for your pre-flop stats, I would start raising more from the CO and Button. Overall I wouldn't worry too much though, it could easily be variance.