Me and my partner DIDNT plan to have sex. He penetrated me for 5 seconds and felt pain and we stopped. He knows he did not ejaculate in me or at all and he had his hand on his penis and felt nothing on it. I took Plan B 24 hours after just to be sure and I also had finished my period two days prior to the incident and was not fertile or ovulating when it happened. What are my chances of being pregnant? Should I be worried? And when will I know for sure?