Am I pregnant?! I'm freaking out! Help!!

My boyfriend and I have had sex 3 weeks straight out of the month.. But he never finishes in me. My "period" (which is ALWAYS on time never late; never early) decided to come early.. But it wasn't regular period blood. It was like old blood. My period always comes on the 5th-8th always. It's been like that my entire life. But this time it came on the 30th. I have a 28 day cycle, I believe. I had my normal period on the 5th. And then the other "period" on the 30th
Well, I go to take a test today and the positive shows up.. But vanishes a little later. Am I pregnant?