Had a root canal over a year ago and I noticed my gums and cheek is swollen with a lump in my cheek but no pain what so ever. What could this be?

Failed Root Canal. This is unfortunately a possibility with any tooth and any root canal. The treatment option is removing the previous root canal and repeating the process. This is often best carried out by a specialist endodontist.
Abscess ? There may be residual bacteria in the tooth or the bone. Please have your dentist take a look.