Shouldn't have let him convince me

He wanted to take the condom off, I said no 100 times and he finally convinced me. I'm so mad at myself. This was 2 days after my period ended and now it's been 2 weeks since. He had already pre-cum before he took the condom off and he did NOT finish inside of me. I'm having sore nips and nausea. Should I worry? I'm not worried about STDs because we test but it's the possibility of pregnancy that's making me crazy. I have some other big things stressing me out and this too, and usually being stressed makes me nauseas as hell so I want to chalk it up as nerves but I still need advice. It's too early to test. I feel like the chances are low but there is always a chance. Please help without putting me down because I'm already disappointed in myself.