I feel like this period is different. Help?

So my whole life, my periods have been pretty damn same. Medium flow, not so bad cramps.

But until last month, my husband and I have been trying to conceive for our 3rd child. Note: that we've planned the other two and gotten pregnant that same cycle, so im pretty sure im really fertile.

Well this month we tried and we were so positive that we had to be pregnant, through out my ovulating week though I did get some cramps which was odd. Comes the day im suppose to get my period, and it comes, which we were disappointed.

Usually the first and second day are light until the 3rd and 4th that are medium then back to light on the 5th and 6th.

Well this time it was medium the first day and have been super heavy for the 2nd 3rd and 4th day.

What went wrong?