not giving mdical advise, but surgical prep typicaly contained a super clean out. Ill never forget that part.
that had a few intentions. first, remove all solids from your GI tract. the second was a heavy antibiotic, basicaly steralioze your innards. in the event of a nick to the bowel, the doc didnt want an infection.
now, your dealing with getting back to normal, and everyone is different. call your doc, see what they suggest.
also remember, the 'spceter' muscle is the one that assists in urine and feces retention. it is the shut off valve. it was ' modified' in your surgery. its going to take a bit of time to heal, regain control of the 'shut off valve function' and feel normal again.
call your doc, get his opinion and recomendations.