Herpes??

Ash

I'm going to be very blunt here. My boyfriend was eating me out the other night which was great, but the next morning we went out and I realized he had a cold sore and he didn't tell me and I hadn't notice the night before! So I've been worried that I might contract genital herpes.. now i just found a very small sore on my lips, it looks more like an ingrown hair that "popped" but I'm not sure! What should I do??