Help! Decidual/implantation bleeding? (TMI)

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On Thursday my "period" came as expected, but only lasted 24 hours and it was light-moderate, bright red with a few cramps and clots. I had no bleeding on Friday or Saturday.

We had sex this morning (Sunday) and when I went to pee, an entire gush of pink-red-brown blood came out. This is not normal period blood (its runny) and I'm not having any pain. Idk what this is tbh. Any ideas?