You do not need Plan B. Unless sperm comes in direct contact with your vagina there isn't really much chance for pregnancy. You can take a test two weeks after this happened or just wait for a missed period, but I'll bet it comes out negative

As for your friend, its actually not a bad thing she's using the pull out method and birth control pills. She's not having unprotected sex-- in terms of pregnancy-- and she's obviously trying to be fairly safe. How long has she been on birth control. How long was she late in taking that pill she missed? Was it the first pill of the month?

Whether or not she needs Plan B depends. Usually one pill isn't a problem if she always takes her pill correctly, or unless its a pill within the first week (especially first few days) of a new pack.

Plan B side effects vary, but some women experience headaches, cramps, or vomitting. You should also expected irregular periods for the next 3 months and spotting between periods is normal as well.