<s>[INST] Hi Doc I had a heavy night drinking got up the next day and found a small round red rash on my right lower back it was very tender and sore it only hurt if I cough or breath in deeply. It also was uncomfortable to sit, if I tense my muscles I can really feel the pain What do you think? [/INST] Hi, In my opinion, it could be a furuncle which is an infection of a hair follicle. If treatment is not initiated, it could lead to a systemic infection. Please do consult your Dermatologist to confirm the diagnosis and to initiate the treatment. Hope I have answered your query. Let me know if I can assist you further. </s>