Ovulation bleeding

Hi guys! I wanted to hop on here and hopefully get some peace of mind. My husband and I are currently TTC baby #2. I’m on cycle day 15 and I should be ovulating around this time. I have been having lower back pain, cramps, and bleeding for the last 3 days. The bleeding is minimal but I see it on the toilet paper almost every time I wipe. I assumed that this was all due to ovulation, but I have been taking ovulation tests each evening and they have all been negative. I’m really confused about what is going on right now. Has anyone else experienced this? Any insight would be really appreciated!