Jennie,
I can't sugar coat this for you - yes it will get better for a little while as recovery from surgery is fairly quick (unless there are infections and other complications). Just about the time he he feeling a little better then they will slam him with the radiation and chemo part of the treatment and that is far worse than the surgery part. He'll have a few weeks before the radiation effects set in then the real nightmare will begin.
Surgical recovery - about 3 weeks.
Radiation and chemo recovery - about 6 months.
I would keep the visitors to a minimum and DEMAND better pain mamagement - it is a PATIENT RIGHT! He should be getting oxycontin, demerol or morphine at this stage. Probably a drip that he can self administer as needed with a push button (PCA). The pain scale is 0-10 with 10 being totally unbearable - use those terms with the nurses and doctors they understand that.
see:
http://www.cancer.gov/cancertopics/paincontrol/page2 See page 9 in the link below
http://www.cancer.org/downloads/CRI/NCCN_pain.pdf