When will it be back?

I stopped taking birth control last March 9th. Everything I've read up on says you should get your period 2-4 weeks after and others sat it can take 3 months to get. I finished out the pack though placebos and all. If I count from the day I stopped birth control it would be 4 weeks and 1 day . If I do it based off of when I got off my period from it, it would be 4 weeks on Thursday. Which one should I expect it to come near? I have had lots of sex since too so how possible is it that I'm pregnant?

UPDATE' I just went to the bathroom and have light pink blood when I wipe but not in my underwear?