Help please!!!!!!

I have had my mirana removed on the 20/01, I had a few hours of red spotting a week later, then 2 days after that another few hours of red spotting. On the 9/02 I have a few hours of a thicker brown spot again for a few hours. I have had nothing since. I have had unprotected sex since tribal, it does feel like pms symptoms since week 2, taken preg test on the 8 feb and negative.. Do I take preg test again if so when