Sounds like you are having bladder spasms, likely due to the manipulation of your bladder. It should improve, but since it has been more than two weeks, you may need an antispasmodic or something like B&O suppositories (belladonna and opium). Be sure that a bladder infection or other infection is ruled out.
AZO might help. All opium products are prescription only. If you want to try MJ, I recommend vaping. Quick action like smoke, but without the smoke. Edibles are more long lasting, but hard to tell what the best dose is, because it takes so long to take effect.
But, be sure to keep your surgeon in the loop. When I had serious tailbone pain with sitting, it turned out to be a presacral abscess. After a month of this pain, I spiked a temp of 105, landing me in the hospital for two weeks. Your bladder issues may be related to something nearby, but not the bladder. The point is that your pain should be gradually improving if all is well.
I always had bladder sensitivity post op...with my 1st pouch surgery they did a contrast study at 30 days post op because I was dribbling too and they were afraid that something was going on...it resolved itself (it was often the irritation from the catheter being in place for so long).
Now after over 15 other pouch/abdominal surgeries I don't panic...it is usually resolved within a few weeks...if not, I start with an ovule (the OTC stuff for mild irritations/yeast...)
I then move to cranberry juice and finally if still not resolved ended up on antibiotics.
I get the pressure, need to pee constantly and never feel done feeling.
Often it is due to general swelling in there too...it takes time.
In my case, unless there is pain and/or fever I don't worry too much...I just allow time to heal me.