Need help in understsnding this

My LMP was 8th September lasted approx 5-6days. According to the app I ovulate today 21st September. I don't know my cycle length as I was on the pill for so long so I've did the average length which is 28 days. My ovulation tests are negative from 19th. Went to the toilet and wiped. This the start of my period coming? This bleeding implantation?

ovulation tests are negative the 4th is slightly darker. Taken 20th 11pm. Have I missed ovulation or has it still too happen?