Skipping the last placebno pill I don't think would matter to much or really effect your cycle to badly. I now of some people who only take 4 placebos and start a new pack just to make their periods shorter. So I really don't think anything horrible will happen.

Everything will be okay. Just don't make a habit of getting off schedule (ie starting packs early and/or late). This one time it will be fine. It may throw your menstrual cycle off slightly but will eventually become normal after a month or two. If you are worried about the day difference making your birth control ineffective, don't worry. Only if you begin you skip pills and become irregular will your birth control be ineffective.
Hope this helped.
Natalie

No shouldn't matter. The docs tell you that if you drop or lose a pill just to take the next one and shift your schedule by a day. You're ok!