Help!!! Could I be pregnant??

Okay, yesterday I had sex with my boyfriend. (This is my only my second time with him. He was my first.) He thought he had his own condoms but he ran and out and didn't remember, so he used his roommate's. The first condom we used broke, and he noticed; he didn't cum. The second time, the condom broke again. We felt a difference but we didn't think about it until he came and was pulling out. We panicked and he bought me a plan b and I took it within the hour that it happened. My ovulation window is over but I'm still scared that I might be pregnant. Can anyone help me??? Just advice will do.