Several months ago I contracted a severe case of cellulitis which put me in the hospital for several days. Today, after a week with a sore neck and shoulder, and running a fever on Monday night (which I attributed to a flu), I noticed some tenderness on the same leg (as my cellulitis) accompanied by a swelling of the lymph node in my left groin. Is it possible that the infection is back? Or, perhaps, never completely went away?