You have not really provided alot of information. "Full historectamy?" You mean "full hysterectomy."
For starts, I would consult your OB/GYN physician or your PCP/Family Physician.
To me it sounds like it is a situation for your OB/GYN physician.
Lastly, pain medication for your BACK is just that, medication for your back.
may u has problom in site of operatione.g; infection, injury to urinarry bladder or remanant of operation must do u/s to know the cause
Ditto to the above comments. Perhaps the pain is due to scar tissue forming or a kidney issue or who knows what? It might be something related to your previous surgery or it could be something completely unrelated. Hope your doctor can sort it out.