I have been on the depo birth control shot for three years and havent had a period the entire time, i dont bleed during sex, but for some reason every time i masterbate i bleed directly after like as if im spotting and it only last like 10 minutes usually. i recently got screened for std/sti and hiv and all my tests came back clean. and when i masterbate im only rubbing the clitoris and not inserting anything actually into my vagina..so im wondering why this is happening? and if its normal? im currently single and not sexually active so its kind of upsetting that i bleed every time i try to satisfy myself