That's exactly what happened, the lovely and very kind sonography lady said that it's hard to see on an ultrasound because if the bladder is full, it's a black hole and if it's empty it closes back in on itself, I understand that maybe this is a box ticking exercise.

my worry is that my GP is utterly useless and I won't get any further help from them and I will be left to worry further, they never follow up even though the lady I saw said she would suggest a procedure that would use a camera to have a better look,is there anything I can do? I have to wait for at least 45 mins to 1.5 hours to get through to my surgery and even then I'm not guaranteed an appointment, I feel utterly bereft