Depo And Pregnancy

My husband is in the military and i was on depo and i recently 3 weeks) decided to switch to the mirena, but i couldnt get an appointment as soon as i thought but the hospital messed up my records and wasnt sure of my window, my husband and i were pretty sure but now my nipples are really sore he cant even touch me but ive read that it takes 3 months to get pregnant after you get off the depo and i was on it for three years, weve been using condoms but well everyone knows about condoms..im hopeing the tenderness is just a side effect of coming off it, i also bleed for one day and i cramp off an on but we are so not not not ready please help