It may happen, but if you had even one day in between pill packs you could be pregnant. Take a home test or go see a doctor to be sure.
my friend actually bled for twelve days when she was switching between b.c. and had horrible cramps so be careful!
Yes, it is normal, but you are also more susceptible to becoming pregnant when you are switching birth control pills. It is best to wait about a month after starting a new brand before having unprotected sex.