What Are The Chances Of HIV Transmission Through Unprotected Sex?

Hi. I am a female and I had sex with a man who says he is HIV negative. I don t think he has actually been tested though. I insisted that he use a condom because I am terrified of catching something. So he had a condom on but he decided we should switch positions. While I was switching positions he took the condom off without me knowing. We had unprotected sex for about 2 to 3 min before I realized there was no condom and I made him stop. He did not cum in me but I don t know if there was any pre-cum or not. I am terrified right now to the point that I feel sick on my stomach. If you could give me some advice it would be greatly appreciated.