"i&#039;ve been on the shot for 5 months now. when i first got the shot, about three weeks in i started to bleed like normal period but then got lighter and lighter and continued for 3 weeks. eventually it went into light spotting about every 4 weeks for a few days. i also will get a lot of sharp pain cramps that will last a few minutes every now and then but this happens randomly. other than that i have no side effects. the doctor tells me the spotting and cramps will stop as my body gets used to the shot."