Im On Depo And Its Been About A Year Now

Im on depo and its been about a year now close to a year and im not allergic to anything and never broke out or anything unusual about my skin but this past weekend ive gotten these tiny red bumps on my hands and they spreaded on my arm a little then i felt them on my whole thigh it spreaded and they dont itch or anything they just continuely spread everywhere...and its unusual this never happened to me is it my depo or... Something else