Talk to Gynecologist on Menses,pregnancy

Hey! I want to consult a gynecologist. After being married in January 2017, my menses has been disturbed. They were usually of 5 days(2 days heavy bleeding then gradually less) before marriage. But now they're of only 2-3 days. And for last 3 months they are like no heavy bleeding but very light. They start with dark brown spotting thread like then after 1 or 2 days, menses starts. Me and my husband are trying to conceive for last 5 months. Also, I've bad lower abdomen pain and sometimes stomach ache. But it gets severe sometime not only during menses or before but the whole month. Kindly let me know with any condition that might be related. Thanks