How long can I expect my abdomen to be swollen after surgery?

Surgery 3 weeks ago. 38 years old, when I was 18 large hernia in my groin, repaired with mesh, a year ago I started getting a lot of pain and a lump appeared. Surgery 3 weeks ago mesh coming away, cist had formed around a nerve, Surgeon cut out some of the mesh, the cist and the nerve. I am now over the majority if the pain, however I'm left with a very swollen abdomen which is tender to touch. I am a uk.size 8 normally and now look about 25 weeks pregnant, and feel it. :-( which I am 100% not.