Well, I am not a doctor but I heard that time when period usually comes can change a bit coz of fasting (which was based on water espessially).. Anyway, I DONT think something dangerous for ur health could happen.. Ok, how do u feel in general?... If u feel normal or even great then - no worries... I guess u need to wait untill the next month and see what will happen (I am sure everything will be fine and, who knows, may be during ur next period u even wont experience unpleasant feelings at the bottom of ur belly during first dayof it!!)... If u r sure that it cant be pregnancy then I guess no worries untill u next month period... Try to FEEL ur body, dear!.. How do u feel now?.. And poss it will be an EXACT answer u r looking for..:))