How painful is cystoscopy procedure?

Not terribly. It's usually done in office without anesthesia. A bit uncomfortable, but nothing to be overly worried about.
Not very. If the procedure is done properly, and local anesthesia can be used, the ordeal is not that painful at all. Hopefully, if you need the procedure, it will not be painful for you. Best wishes.
Bladder Envisioned. Cystoscopy, or a look in the bladder using a scope, can reveal the source of bleeding in the urine, pain in the bladder, weakness to the urine stream and other concerns. Looking in with a flexible scope creates less pain; however, if a rigid scope is needed, most men are best evaluated under some anesthesia. Expect burning for 1-2 days after the procedure and possibly some urgency to pe.