What Causes Tingling Sensation In Labia?

After an intense workout yesterday, I noticed a tingling sensation in one small area of my labia, right outside the opening of my vagina. Now it s still tingly and irritated, and painful when I touch it. It s very small and hard to see, but is a single raised reddish bump, no breakage if the skin or ulceration. Since yesterday I have also had painful urination, although this is not at all uncommon for me. I was tested for all stis a year ago and was clean, and have the same partner since. He does, however, get cold sores.