POSITIVE OVULATION TEST AND VERY VERY FAINT LINE ON PREGNANCY TEST

Hi everyone I had a stillbirth 8 weeks ago and been ttc for 5 weeks since my hcg levels went down to zero I had a peak ovulation test on sunday 13th September. So I baby danced on that day I've been needing to urinate more often I've been feeling sick and had stomach pains I've took an ovulation test again today and it came back as straight peak yet Friday when I took an ovulation test it wasnt even showing as high so I then took a clear blue pregnancy test which came back negative so I then took red die pregnancy which came back as a faint positive and then a red die and that came back negative what the hell is going on as I'd only be 7dpo?? Thank u x picture 1 is the ovulation tests and the two pregnancy tests which are negative the last two pictures are a test with a very very faint line thank you x