Not only can you get pregnant, it sounds like you may already be pregnant.
Just so you know in the future, once you go off of hormonal birth control (the pill, whatever) you are only protected for a few days. It wears off quickly.
Again for future reference, condoms are not terribly expensive. The good ones are not that bad and the person you are with should also take some responsibility. Maybe pay for the condoms??
For now you should consider going to a Planned Parenthood clinic or somewhere you can find out if you are pregnant and figure out what your next step should be.
Hang in there. I will be thinking about you. You are not alone.