maybe it's a stupid question .... IDK

So this month I had my period at my normal time 01/11 but only lasted until 01/12 (later that night it ended, stopped as if it never happened.) on 01/14 my husband and I were having sex and I was bleed a little bit not too much. Before I even got my period I would like to mention that I did take a pregnancy test and it came back negative .