TTC Advice Please, Could i already be pregnant?

Hi all, yet another am i pregnant/ttc questions....anyway, i am currently ttc, and came off the pill brevinor 5 months ago now, and have had a withdrawal and 1 proper period. however last month my period came 6 days late and was due on the 6th but obviously came the 12th, anyway, i took a couple off tests and each said negative. My period came on suddenly in the morning followed by bad back pain, with quite string cramping mainly in my right ovary area, however this then went away and didnt return, but my heavy-ish bleeding lasted 3 days and then barely nothing for a day and half just browny blood, it only lasted 3 & half days, when it usually lasts 5-6 days.sorry for the information. this concerned me, and now wondering whether i could already be pregnant? but im not sure if you can have this sort of bleeding while pregnant, so im just wondering if anyone else has experienced the same or know someone who has. i also keep getting twinges in my right ovary, and when i cough my ovary area feels sensitive so i have to hold it. but this only happens when i have a bad cough now and again through the day. no other symptoms. sorry for the long paragraph.