I haven't checked this board lately and I wish I had. Have been having the same issues since my resection last March. Felt great for a while and then the tell tale pains started again. I wrote about them a while ago.
I honestly thought having the surgery would eliminate the worry, and for the most part it has, but today I am on the old stand by of cipro - flagyl as yep I have diverticulitis again( second case since the surgery) Sigh.. I have watched my diet, ate and took fiber, only drink water and I am a vegan.
I am sure I am looking at another surgery.
I did have what they thought was intussusception after the surgery but a different colo-rectal surgeon did a flex sig and said that it was not. I was told by this colon surgeon that it takes up to a year for everything to finally settle down and to expect issues but if you still have diverticulosis then chances of having repeated episodes of course are high. He said it was not abnormal for most anastamoses to be "pouty" and act up. He told me the same thing yours told you, if you have pain go to the ER and that it is more serious after a resection due to not having the diseased part of the bowel. Of course I did not believe him so I got yet another opinion from a top doc in GI medicine at the University of Michigan who told me the exact same things with this addition - when it comes to fiber one size does not fit all, meaning for some people 10 -15 is more than enough and others need 20 -25. Both of these specialists told me that for women the max should be 22 and for men it is the 30-35 range.
All this being said, I am with you I am tired of the lower left pains and what I should and should not eat etc. Since this is a somewhat older post, I hope you are ok.