Hi. I'm On Day 6 Of My Period And Have

Hi. I'm on day 6 of my period and have just found a very strange small dry fibrous clot thing in my pad. My flow is lighter now and my periods have been different over the past 16 months since stopping birth control. Myself and my partner are trying for a baby. Typically my flow is heavy for the first two/three days and then progressively lighter until it stops at around 7/8 days. I have been feeling tired although put it down to poor diet and have had cramps which is normal but feeling almost a pulling in my lower abdomen. Always one sided but not the same side. More painful when I move quickly like when standing up. May well not be linked but starting to worry a bit...