Sorry to hear of your continued pain. I'd definitely not try to "tough it out" by going off medications, though possibly you may need something different prescribed for you at this point. I used to suffer a lot from bladder spasms, even after just getting a cystoscopy, let alone a TURB; as you describe, they were worse at the end of the pee than at the start. You are still healing, and your bladder is likely still mad at you for what it's been through! As well as anti-spasm medication, I used to find sitting in a hot bath very helpful for spasms. Now that I've had so many cystoscopies, 2 TURBTs, and a full course of BCG, I find that my spasms are way less, and very short-lived; I did, however, have to get the BCG concentration reduced to 1/3rd part way through the maintenance treatments.
As to the sleep problems, you may be having to wake up to urinate when you are at critical points in your sleep cycle, making it harder to get back to sleep.
Ann