I Think I Have Interstitial Cystitis. I Have Been Prescribed

I think I have interstitial cystitis. I have been prescribed Nortriptolene increasing dosage from 10mg to 50mg at the moment I am taking 20mg 2hours befor bedtime due to increase to 30mg on Tuesday. I had a pelvic floor repair posterior last October. The pain I am experiencing is around the urethra and vaginal area I have frequency of micturition Its is a intense throbbing pain that comes in spasms causing sleepless nights this has been going on now for nearly 2 months I have an ultra sound appointment but not till the 23rd ofOctober should I be pushing for an earlier appointment or should I try and book one privately and is this pain something I will have to put up with. I don't drink I don't smoke and I don't have caffeine in my fluids that I intake. I am in a lot of pain. Please advise Thankyou.