I normally have a 40 day cycle, but this month is the 1st time my period has come on CD23. it isn't spotting but bleeding like a normal period, at first I thought it was (mid-cycle) bleeding, as on day CD21 it was a light brown colour. what throws me off is on CD20 I had a positive OPK test. Is it possible to have your period 1 day after a positive OPK test? We are trying to conceive, My husband and I did have intercourse during CDs 20 21, do u think the sex caused the ovary to bleed while trying to release?