My cycle is so off... I got the depo shot Jan 11 2016. My period before that was normal, Dec 24-29. My cycle has always been about 35 days. After I got the shot my cycle went to 60 days.. Got my period Feb 23-25.. Only 3 days, normally mine are 6.. Now I just got my period Mar 20 and it's still going.. On day 7.. It's super super light, no symptoms of a period just dark blood.. I'm assuming it's just old blood but what is going on with my cycle? Help.