I'm having a cystoscopy while under anesthesia this Wed. How much pain should I expect from this procedure?

Very minimal if any. Usually diagnostic cystoscopy,especially in females,is done under local anesthesia. If a biopsy will be done you may have a little discomfort on urination.However,cystoscopy is not normally associated with post-procedure(notice I am not saying post "operatjve") pain.You should be fine:)