<s>[INST] over the last 4 days I have noticed a lump just under my left bum cheek, it is painful when I touch it or move it, it looks slightly red, but that maybe from where I was trying to look at it, I think its too big to be a boil or a spot its about 2cm. I am 19 years old and female do you have any idea what it is ? [/INST] hi.it could be an inflammatory reaction, a cyst or an abscess based from your description. it is best if you consult with a doctor for physical examination. management will be directed accordingly. also, maintain a good hygiene, do not scratch/manipulate the lesion, as it might get infected.hope this helps.good day!!~dr.kaye </s>