What Causes Excess Flatulence,abdominal Cramps And Frequent Urination?

hi doctor,i am a young adult, in my 20s. i normally have unprotected sex with my partner 7 days after my prediods, because we had learnt that a woman cannot fall pregnant 14 days after her period, so to play it safe, we normally keep it at 7days. and for the other days, we normally use condoms. he has a lot of semen, and his undies always have spots of semen. even when his not turned on, semen would drip from his penis. so one day we had sex without using any protection, the following week i did a pregnancy test and i tested negetive. but now im farting alot. every 10mins. i get weird cravings, and weird cramps, i urinate often lately. i did a pregnancy test again and i tested negetive. is there a possibility though that i could be pregnant and that i dont know it?