Smell?

So I had unprotected sex with my boyfriend for the first time on Thursday, Friday night I masturbated and used ky jelly for the first time with my toy. Saturday night I noticed a really sour metallic smell and had chunky discharge. I should be starting my period in a day or too also. I'm just worried about the smell, I have never had any sort of problem with it before. What could it be? I have no itching or discomfort,the only symptom I have is the smell.