opinion

So me and my partner have been having unprotected sex multiple times a day some weeks it's every day some weeks it's every other week...my periods are not regular at all so idk when I ovulate....November I got my period on the 7th and it's lasted 6 days which it normal last 5 or 6 days in December I got my period the 18th and it only lasted 4 days which is weird it only was 4days long and this month I have yet to get my period I have all the cramping and symptoms of a period for a week and a half now and I only get cramps the first day of my period never before my period I took a Prego test last Friday at 4 pm and it was negative and I took another one today at 340pm and it was negative again..... wat should I do????