Freaking out about weight?

ok...My normal weight has been anywhere from 144-145 and I am 5'7...since feb my weight has fluctuated from 139 to 147!! I am supposed to start my period today and the week before I start my period I bloat really bad and tend to gain a few pounds..BUT..tonight I get on the scale and I weight 151.5!!! I have been going to the gym and running 2 miles and sometimes doing the bike and eliptical and have taken one or 2 classes at the gym..and well...I have been eating alittle more then usual...but nothing outragous at all..is it outragous to gain that kind of weight?? especially when I go to the gym and run like that?? do you think its just period weight?? or should I be concerned??Freaking out about weight?
sounds like u are building muscle which weighs more than fat. don't panic! muscle burns more calories than fat, so it will even out and you'll actually lose weight. everyone i know who starts exercising, initially gains about 5 pounds before they start losing. keep up the good work.
any chance ur pregnant?? unless u got ur period...?
try eating more fiber about 20-30g a day