What is this?

Im not sure how many DPOs I currently am as I don’t get regular periods.

On Sunday H and I had sex and I bled afterwards a little bit, but it was bright red. Monday-Today I have had brown/light pink when wiping but not enough to even fill a light tampon. I thought it was a period but now I don’t know. I’ve never ever had a period that light.

Should I test in a week or so?