Could Swelling In Face Be Due To Sinusitis?

Hi, I recently noticed a swelling on the side of face (between right eye and right ear). I was having little difficulty in opening mouth also. It was as if there was some tightness there. I consulted a physician, a dentist also. Physician suggested a TM Joint x-ray and advised to consult a ENT specialist. X-ray of TM joint did not detect any problem. ENT specialist now has advised a PNS water's x-ray and blood tests - cbc, rbs, hbs off etc. Moreover I observed more hard swelling after I talked for the whole day as my work is like that. Now the swelling has come down and has inceased on my cheek. What could be the reason? Has it got anything to do with sinusitis? or is there any major problem?