Pink spotting 4 days after AF.

Has anyone ever had this happen before? I had AF July 21st-25th and late morning today (7/29) I had pink spotting only with restroom use and again around 130pm with restroom use. My husband and I are trying to conceive and did have intercourse 7/25, 7/26 & 7/27. However thought nothing of it, since it's so close to AF. Help, anyone?