LH surge, very short period,negative HPT- HELP

Hi ladies! I am new here and would appreciate some insight or anyone else that has gone through this. Long story short my cycles are pretty regular and they are always about five days with the first two days being so heavy I have to use like the super plus plus tampons and change them every hour. I usually pass clots and everything. This cycle my period was about 2 days if that. It started 9/28 and ended 9/30. The first day which is normally my super heavy flow, I only had to change my tampon once. Day two only once and D3 was just spotting. I had moderate ovary cramps during my “period” which isn’t normal. I immediately took a pregnancy test because I thought maybe it might be implantation bleeding but it was negative. I thought what the hell I will take some OPKS. My lines are getting darker. I know I ovulated last cycle. Any idea why there is such a big LH surge immediately after my “period?” I’ve attached the OPKS. Any insight at all or comments would be SO appreciated!!!