If this is a newer problem for you, then the first thing I'd want to rule out is a bladder infection. You don't have to have pain or bleeding to have a bladder infection. In fact, two of the most common symptoms of UTI are frequent urination and/or the sensation of having a very full bladder, even if there is very little urine to pass. (I've had my fair share of UTIs, so I would know!).

If a UTI has been ruled out, it is true that the bladder and pouch are in very close proximity to one another, and that a full pouch can push on the bladder. It's one of the reasons why many pouchers have difficulty not "doing a number 2 when you only want to do a number 1."

That being said, your experience of frequent urination and having a sensation of a full bladder when your pouch is full, is definitely NOT typical of most j-pouchers. If you pouch is newer, one thing I might consider is whether or not you have scar tissue which is amplifying the problem, or if a nerve might have been nicked during surgery. OR, if your surgery was especially recent, I would want to rule out whether there might have been infection or local trauma to the bladder from catheter use (you can pick up a pretty nasty infection, not to mention local trauma or irritation, from one of those). It's also a possibility that your urinary tract symptoms have nothing to do with the pouch and are a completely separate issue.

The short of it: I would have this looked in to, sooner rather than later, especially if it's a persistent problem and is bothersome for you.