Well, basically phlegmon is acute, pus and inflammation of subcutanous tissue. Are you by any chance on an immuno-suppressant? I've been told that immunosuppressants can suppress or "hide" a fever. Which possibly answers why when so many times when I feel feverish my temp is "normal", i.e, 97.x to maybe even 98.x, few times even 99.x, yet other times when I feel just fine my temp is sometimes as low as 94.6. My "normal" temp seems to run around 96.7 to 97.4. I've never thought to connect my temperature to the dose of Imuran I'm on at the time. (And, yes, I've double-check between regular mercury thermometer and digital thermometer).
Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.