Should I finish my current pack, and...?

Hi,

I have been using birth control pills for about 2 years now. I use one that has 21 active pills and 7 placebo pills. At the end of my last pack of pills, I went abroad and didn't manage to get my new pack of pills from the pharmacy. My period started while I was abroad. When I returned from abroad, I immediately got my new pack of pills, and took the first pill 10 days later than I should have. As precaution, I have been using another method of birth control, so I am not worried about pregnancy this month.

What I am concerned about is the next set of pills I will be taking. Should I finish my current pack, and start the next pack when I finish the last 7 placebo pills? I am currently in the 4th week (placebo week) of this current pack of pills, but my period is late. I had cramps a few days before, though with no bleeding (the time I would have had a period if I had taken my pills correctly). I'm not sure how to proceed. Advice would be appreciated.