Possible STD ?

Not getting into gory details but I had unprotected sex about a week ago..started my period 2 days after and ended today. Yesterday I experienced some itching and discomfort in the vaginal opening but no discharge or pain during urination. Today the discomfort has subsided, I think I was being a hypochondriac because of the fact that my last tampon change was dry and I had a hard time relaxing to get it out so maybe things just got irritated? But to be on the safe side, with STD's is the pain and itching constant or a come and go? I'm getting tested anyway, this is just to appease my thoughts for the time being.