Unusual bleeding

Hey guys, just looking to see if anyone has any insights on this. So I got my periods today, basically 2 days late and I'm always very much on time and regular but before that I had cramps for a week and felt weird and off so I took a pregnancy test, which I thought had a vvvvfl at the time.

This period has been the most painful period of my life, I usually don't have cramps really and also don't really have much clotting but this time I did. Last month we had officially started to TTC. I'm just wondering if anyone else had experienced this, what could be the reason?