Irregular cycle on BCP

So I screwed up my BCP this month. I'm on lo loestrin and accidentally had my pack upside down, and took a white pill on my third day. The next day I realized what I did and took the blue pill from the day before, alone with the blue pill I needed to take that day. Other wise, this month I've taken every pill at the right time. Today was the last day of my pack and I still haven't gotten my period. It's 15 days late. I was even paranoid enough to take a pregnancy test, and they were both negative. Tomorrow I'm supposed to start taking Junel Fe, but I don't know if I should wait to start it until I get my period, or start it immediately tomorrow at the same time.