Suggest Remedy For Spotting After Intercourse

my name is whitney im on the norplant shot been on it for 2 years wanted to ask if substances can affect the shot some how were off i have 2 kids recently ive had unprotected rough sex notice ive been spotting afterwards thought i started my period but lasted a day idk if the rough sex cause the bleeding idk need Answer im not ready for a kid im i suppose to use condoms even if im on the shot like i said been using