Birth Control Confusion, need some help?

ok so ive been talking birth control for about half a year now ..a little bit more, and everything has been fine and dandy, worked perfectly, no need to worry about that. my problem right now is that i thought i had another pack for one more month and i don't. So ive been scrambling this last week to try and get my next pack, but its been 5 days now since i haven't had anything. Im a sunday starter, and ive been trying to read if theres anyway i can start taking it once i get my new pack, but the instructions are confusing me. it says that if i miss three or more pills to keep taking the rest for the week, but on sunday to throw out the pack and start a new one. At least, that's what i think they're trying to say. I know i made a stupid mistake by not making sure i had enough, but i need to know if this will work or if i need to wait a month until my period to start again. I really hope not, but if i do, how exactly do i know when to start, since i hear its very common to skip a few periods when you go off the pill. I am very confused and really just want to fix this. Does anyone know what i should do?