yea, it generally takes you off yourself after a good sex session, so its normal to be a little tender afterwards especially if you dont have sex too often, or it could be that your partner is a bit too rough during the session just take it slower, more passionate so you dont hurt each other. Sex can be crazy and its worse if you dont have it often enough your more sore, i was like that at one point.
Contraception is no connection to the effects of sex!!
Some women are sensitive to the chemicals inside a mans seminal fluid and many women develop Thrush afterwards which is just an imbalance of the natural bacteria in the vagina being disturbed by the semen, this is very common in women, so just both takecare.