I had a period on Feb.3rd and it ended on the 8th. Me and my boyfriend had sex on valentines day and there was blood. Only a little and it was brownish. I waited a day and called my nurse on the 15th. She suggested to take a pregnancy test. It was negative. Me and my boyfriend had sex again on the 16th. No blood!!! Im confused. Please help. I'm 24 yrs old of that helps. With no irregular periods. And I have a 3 yr old daughter.