Can untreated yeast infection cause sores?

I had unprotected sex with a guy about 40 days ago. Literally the day after the encounter, I felt burning in my vaginal area, thought I had a yeast or bladder infection or even STD. I continued to feel ichy and burning, but it wasn't anything too bad so I kind of forgot about it. However, today I noticed that I had a certain spot on my vaginal flaps that was particularly sore and it seemed inflamed--but I couldn't get a clear look at it really. I went in to get STD tested and had them take a look and results came back positive for a yeast infection and I took a pill. I feel like I might be getting a sore, from what I can see it looks like a red spot (not bump) and it's kind of ichy/sore ONLY when I touch it though. Could this just be from me leaving my yeast infection untreated for 40 days? Or is it an STD? (I'm getting results back for chalmydia, ghonnorea, herpes, syphillis, etc. in a few days, I just need to know if it is a possible result from the yeast infection)