No sign of period coming, though it was due a few days ago...help?

This happened to me before too. It's really annoying. Your period might be doing a cycle change. Another reason could be because you are stressed. My period didn't come for almost 1 1/2 month because of the stress that was going on in my life. Don't think about it and just wait. It will come. If it doesn't for another month I would ask your doctor. You might have another medical problem.