<s>[INST] I had some swelling on left shoulder for last 8-10 months. It used to smell very bad whenever I would touch it. In last few days, little pus started to come out which smelled horrible. Yesterday, I squeezed out a lot of pus from there, but there was still some left. Today morning when I woke up there was even bigger swelling and there is pain also. However on touching, it does not smell but hurts. This pain was never their before, however there used to be some itching earlier.Could you please let me know what is wrong with me and how I could fix it. [/INST] HI, thanks for using Chat Doctor Based on your description it is possible that you may have a cyst in that area which may have become infected. A cyst is a sac that can form in different aspects of the body. The exact cause of formation is not known. You need to consider visiting your doctor for treatment. This would include incision and Chat Doctor. Antibiotics would also be needed. I hope this helps </s>