Could I be pregnant or just a weird period

Vicky
My Flo was supposed to start last Monday. Couple of days prior I started having strange cramps. Then had one day where When I wiped there was some brownish 'blood'. Since then no blood and still having strange periodic cramping daily. Makes me think I am going to start my period. Would stretching of the uterus be causing these cramps? I think I'm going to go buy a test....