Nipples hurt-so bad!

So a few days ago my nipples started hurting terribly bad, to the point that wearing a bra, anything brushing against them, or my fiancé touching them hurts so, so bad. I haven’t had my period since last April because I had the depo shot, the shot expired in August but still haven’t had my period. Hoping for a baby but not really sure what’s going on, any ideas?!