Despite the British Menopause Society insisting that medics are being educated it obviously isn't getting through to many

: because your situation of a GP not knowing much or wanting to learn, is more normal than it ought to be.
Why did you stop the HRT regime? Also if you can take a cancellation appt for the hysteroscopy i.e. when someone no longer wants the appt or doesnt' show, then let the Dept know and they can contact you. They may also know how long the wait is likely 2 B.
As oestrogen levels drop the body may becoem dry : inside and out; skin, deep in the ears, vagina, nostrils, scalp and muscles may become lax = aches and pains. If this is a sudden onset of pain then at least listen to the patient? MayB if this continues you could self refer to a physio for advice, do not undergo any manipulation-type treatments with an X-ray of the painful areas.
Your symptoms are familiar to me. Did your GP send off a urine sample to be 'grown' in a Lab. regarding the UTI? This is probably the start of vaginal atrophy, again caused by a loss of oestrogen which is our elasticity. Appropriate treatment really helps with this condition so do read the 'bladder issues' and threads about VA. I would also ring the Surgery to ask for a referral to a dedicated menopause clinic: not a gynaecologist as they often don't know much more than many GPs seem to : as there are waiting lists. VA mimics repeated urine infection-type symptoms really really well and many medics have no concept.
3 weeks late probably = peri-menopause. My periods waxed and waned for years and I knew it was The Change so wasn't particularly concerned. Also I haven't suffered much in the way of flushes but I do have a supportive GP, with a Wife my age ;-).
Some find that keeping a mood/food/symptom diary of use to chart progress. Let us know how you get on.