Hi, I am a 66-yr-old female. I have been prone to "fever blisters" (Herpes Simplex) all my life. Day before yesterday, I felt what I thought was another fever blister coming up just on the inside of my bottom right lip. Yesterday, it was larger and much more rounded, and extremely painful. Last night after brushing my teeth and washing my face, I looked closely in the mirror and saw that it had a white head. I have never had a pimple like this on my lip! I squeezed my lips together, and pus started pouring out. After squeezing it gently with my fingers, it burst onto the mirror. Today, it is smaller but still swollen and sore. What do you think this can be? Do I need to be overly concerned?