I received my third depo provera
injection on time (11 weeks past last injection), but I'm concerned the nurse didn't shake the vial enough prior to injection. She did shake it for a couple seconds, but I've read online that the vial should be shaken vigorously and I've even read that it should be shaken for as long as one minute. Will my injection still be effective if it was only shaken briefly? Or should I use back up protection (condoms) until my next shot?