cold sores

So my boyfriend and I were making out and he was eating me out and then the next day I realized I had a tiny cold sore. I lip felt weird the day before but I didn't think it was a cold sore. So now I'm freaking worried. How easy is it to transmit cold sores into gential herpes. My boyfriend doesn't get cold sores. But I'm just worried because we were making out. And I also read even if u don't have a cold sore visible u can still give someone Herpes with oral... so Idk worried...