Hello, I am going to take an STI test for the first time. In the past I have had cold sores around my mouth but none on my genitals. I wanted to ask if there was a way that an STI test could differentiate between genital herpes from other kinds? I wanted to make sure the cold sores I had on my mouth wouldn't give me a false positive result. Thank you. 

The vast majority of cold sores, probably more than 99%, are HSV 1.  Since you already have HSV 1, you should only test for HSV 2, if you test for herpes at all.  With some brands of IgG tests, there is a high rate of false positives, but LabCorp labs are now using a better test made by Roche which has far fewer false positives.  So if you test for HSV at all, use a lab that uses Roche.  Quest does not---