Crown irritating gums. Cement was found but problem persists, months later.

Had a crown placed 5 Months ago. The pressure was severe when placed. It hurt the tooth next to it, and there was a lot of pressure up through my cheek and temple. The gums have been inflamed, sore and bleeding when flossed and I still sense the metal edge. I tried a oral rinse with no avail. General dentist is wondering now about crown lenghtening. Should the crown be re done first in case the measurements are off before trying something so drastic?