"i am 17 and have been on depo for 3 months. i started off with no side effects for the first 3 weeks, until i was late for my period by 2 weeks, then when i eventually had my period i have been spotting for the last 6 weeks. which is really becoming annoying and making me feel depressed. i haven&#039;t lost my sex drive, but i have had major mood swings and sore breasts for the past 2 months. i feel as though i will keep using depo for the next 2 shots and see if anything changes, because overall i feel as though minus the spotting it is beneficial."