If she went from one pack directly to the other pack, you are correct in thinking that she should finish that pack straight through. Taking the placebo pills after the white week of pills is breaking the hormonal protection at the wrong time.
The two of you should use another back up method of birth control for two week until the hormones are back in her body. After the placebo pills, make sure she starts a new pack starting with the white pills again and doesn't just continue the pack she started before.
If she is not bleeding yet, it may be normal. Sometimes birth control like OTC can lighten your period or make you skip it for a month, especially if she was on depo before which can stop a lot of womens periods while they are on it.
However, make sure to use protection for two weeks other than the pill while her body gets back to normal, and take a pregnancy test two weeks from the last act of unprotected sex just to make sure.