so i was on and off depo for about three years and i have been off for almost a year now and my period had been back to normal for about 7 months now. and i havent had sex since september and my period was coming on time every month. well i recently had sex around the beginning off january and i usually get my period at the end of the month and i still have yet to start my period, but tests keep coming back negative. if anyone can tell me why or what to do that would be great :)