pregnant or just birth control?

I've just started my 3rd birth control pill pack. I read that skipping the placebo pills can make it so that you don't have a period, so I skipped them last month for the first time but I still got my period. I skipped them again this month for the second time but this time I didn't get my period. I am 2 weeks late for it. Is this because I skipped the placebo pills? Or am I pregnant?