i m 28 years old, weighing 50 kgs, and am 5'2" tall. I have always had a flawless complexion. but since i had e.coli infection of the intestine, in oct 2009, i have had a bad acne problem. though the rest of the face is better now, my chin has red, bumpy things, below the skin surface; and a heating-up (not burning) sensation. there are also some pus-filled, painful acne that keep erupting on the chin itself. plz help!!