Pregnant?

This whole past 2 week my bf and I have been sexually active. We've been rubbing each other and dry humping naked. There's a few times he cummed and a few times he's accidentally went in from dry humping but stuck out quickly since it hurts me since he's big and we don't have lube to help ease the pain. Anyways. Today I felt odd.. I took a test incase and got a faint. HOW IS THIS POSSIBLE??? Could it be a false positive? Like wow.. I'm excited, but wtf???