I'm not Smackin, but I'd like to reply anyway. Take it or leave it.

$25 NL 6-max should be very easy to beat with a very straight-forward strategy. Play ABC poker from the first four seats: raise your good hands, fold your bad ones. Use continuation bets on the flop if you raised before the flop (I recommend about 2/3 of the pot). Don't get too married to these hands if you miss though. If you get called pre-flop and then on the flop, you should probably let it go. From the cutoff and the button, limp or occasionally raise with suited connectors and suited one-gappers like 97 and T8. Try to go for straights and flushes with these hands, and play them as cheaply as possible. Finally, you can pretty safely limp any small or medium pocket pair from any seat, and call a raise of 2 or 3xBB with them to try to hit a set. Finally finally (sorry, thought of one more thing) hands like KT suited and Ax (where x is any card higher than 7) should be raised from the button with your standard raise, if there is no raise ahead of you & not too many have limped in.

It's about that simple. It's hard to tell from your post what you are doing right or wrong, and frankly your sample is way too small - and will be for some time to come. A 4 hour upswing or 2 hour downswing could mean anything, or nothing. Just focus on your game and accumulate more playing time.