Upper sternal swelling

It's a well-circumscribed, somewhat soft, mildly tender swelling. It's located right on the bone. I'm not sure what "fluctuant" means ... ????. I've had somewhat of a barrel-chest for about a near now anyway ... I guess due to the emphysema. But this swelling is different.

I have been having night sweats (not every night though), and I also sometimes break out in a sudden sweat during the day for no reason. I don't think I'm having any fevers ... I haven't really checked my temperature. I'm not having chills though. I haven't experienced any weight loss or loss of appetite neither. I do, however, fatigue easily (but again, I've experienced this for a couple years .... I think due to all my chronic medical problems and medications).

The only other "recent" symptom that I've been experiencing more than the norm is headaches. Not severe headaches, just those barely-there type headaches.

I originally thought that maybe I hit my chest on something without realizing it, so I tried putting ice on it. It didn't help. So then I tried heat, but it, too, didn't work.

Any advice you can offer would be greatly appreciated.

Thanks!