Pregnant or not pregnant, help?

Me and my girlfriend had protected sex on November 13th. When I was done I got off and noticed that the condom was on her vagina still and feared that I may got her pregnant so we quickly rushed to the pharmacy and bought Choice one so our chances would be less for her to be pregnant. 10 days passed after that day and she took a pregnancy test and came out negative. Then a week before her next period would come she told me she was bleeding for a while and stopped and we didnt know why was she bleeding. It was December 6th and her period didnt came yet so on December 14th she took the test and came out negative still. Until today, she havent hadher period yet. No signs of what so ever of being pregnant and right now she is having cramps on her stomache (a sign that always comes for her when her period is about to come) and im here thinking is she or is she not. Anyone with good experience of this or had happen to them would like to tell me an answer?