review your play - if you played OK and just got unlucky then do not worry - it is a game of variance - upswings and downsings - when I moved up from 25 to 50 NL I hit a run of bad luck and lost 19 Buy-ins in a week and half.......
in that time I got my money in when I had at least a 5% advantage 85% of the time!!!
I had every sort of bad beat possible... Ace high flush beat by str8 flush or runner runner boat - boats beat by quads...
at one stage there was a run where i hit a str8 and then got flushed 7 times in a row (str8s that is)...
and so on....
if you are playing well - it means it is just 'variance' play good and it will swing the other way ....
(I had 10 winning sessions in a row on PP after that bad run.....)