I had resection back in Feb of this year. It must have taken a good 3 or 4 weeks for the pain to subdue to a level were it wasnt too bad. I was taken tramadol 50 to 100mg every 4 to 6 hours. Even if you dont have much pain you are better taking something if you dont combat it until it is very sore then you will be putting yourself through a lot of unnecessary pain.
As for the D, I was the same it was just continuous and really saps what little energy you have when you are constantly going back and forth to the toilet.
I also had the same problem as yohimbe and my potassium and other electrolyte levels became dangerously low several times. I would strongly advise to get your bloods done once a week and if you feel any tingling or cramp in your hands, feets and other muscles to contact your doc pronto as it is a sure sign you electrolytes are low. I had to back in the hospital twice for this reason.
At that stage I really didnt think would get better and thought I would be in and out of hospital for ever. However, after a good 2 to 3 months after my op things did settle down the D has now stopped although I do take immodium daily for this. I also took supplements for the electrolytes for several months but those have also leveled off to an acceptable level. I've also piled on a lot of weight since the op and fitter and healthier than I have been for years. It can be really struggle for the first few months after your op but I've been there and things will def improve over time.