Spotting?

Hi there momshies, ask lang po sana ako, naguguluhan kasi ako. Bakit po ngspotting ako 2days na twing iihi ako pag wipe ako thru tissue may light blood po. Uhmm. Actually this is is may fertile period. Nagkaroon ako july 9-12, then based sa tracker to this week is may fertile window. Nagdo kami ni husband nung 4days ago. Ano po kaya to?