TWW mystery! Help me!

Heather • Arya Lyn ❤️ Born July 3

Maybe you guys can help me! My BF and I had sex the other night, orgasm for both, and I was at 4 dpo. Afterwards during the super fun clean up, I had really heavy clear egg white discharge with a pretty big clump of light brown in the middle of it. Sounds like ovulation mucus to me but... I thought I already ovulated! What could it be? I can’t figure it out!