Can you get pregnant?

I didn't know that baby oil ruins the rubber of the condom and can have a more likely chance of tearing or breaking. I had sex with my boyfriend before knowing this fact and we used baby oil as a lubricant. He finished with the condom still on and it didn't look like it broke cause all of his cum was still inside or at least I think all of it. I was wondering if I have a chance of being pregnant or its my mind playing tricks on me cause my sister's pregnant.