Period and pregnant?

So I was supposed to start my period on Monday. Sunday I had super light spotting but only when I wiped so I assumed my period was coming even though it usually starts full force. Then Monday it came later in the day just like a normal period which for me is heavy with cramps. By Tuesday my period had almost stopped back to spotting. Usually my period is very heavy for the first 3 days then 1 day light but I still need to wear at least a pad. Has anyone had anything similar and been pregnant? I had a faint positive on a test but it was blue dye so I thought it was a false. Just wondering what could be going on?