dunlow,
You do not say how long ago your surgery was and also, was it a TVH or an abdominal procedure?
Of course, an abdominal procedure is going to take longer to get over than a vaginal one. And if it has only been a few days, you are still going to be very sore. But, if it has been 6 weeks, that different.
From you post, you also sound depressed. Are you getting out of the house, both outside in the fresh air and sunlight, and also out to such things as meetings with friends/family, going to the movies, shopping, etc. Isolation can make the post-op period just that more difficult.
You should, of course, follow your surgeon's instructions on how much activity you should do. And as long as you are within your lifting limits and the activity is not causing pain, you should try to do as much as possible. You have to get the body back into physical shape, and that takes some rehab.
Hope you start to feel better real soon. Good luck.