Yeast infection... Maybe STI😔

Last week one of my lovers called me and told me that he has been experiencing some weird symptoms (i.e. weird discharge and pain when he pees). He told me that I must’ve given him something so that hour I went to the Er and got tested for STI’s. I wasn’t experiencing anything at the time but I just wanted to be safe. Over the next few days I started to feel weird though (I.e. itchy and chunky discharge) yesterday it got really itchy so I went to my friend in obgyn and she told me that my symptoms look like a yeast infection. So I got tested and that is what I had. And I told my partner but he doesn’t believe me... I’m still waiting on the test for the STI just in case it’s something else but he still hasn’t gotten tested either which annoys me. What should I do