tight discomfort at base of sternum after surgery

Had an open repair of paraesophageal hernia and Toupet four months ago.
Am doing well overall, but still having a tight, heavy feeling, pulling discomfort at base of sternum, at the top of the incision. It just feels so heavy and tired in that area.
Talked to surgeon; he says there are lots of stitches there and healing to be done; plus the fact that a medication (Imuran) I am on for another condition may slow my healing somewhat.
This discomfort is worsened if I sit upright for long periods, any bending, twisting movements, etc and it is even causing aching into my back, between shoulder blades.
Surgeon said the worst should have been past at 3 months but I may be taking a bit longer. He was not particularly concerned but I am wondering if anyone else has had pain at base of sternum as long as 4 months post surgery. Thanks for any advice.

Alcie,
Thanks so much for responding. Can you tell me how to go about finding some of your old posts to read? I have tried but haven't had any success. Again, thank you ; you have given me encouragement and I apppreciate it.