Thank you all for your useful thoughts !
I am going to see the doc on Friday afternoon but had the forethought to arrange to take a specimen down tomorrow morning so test results should be in for the appointment.
If this was Who wants to be a Millionaire I'd answer "atypical UTI" that's maybe gone 'up' some, which I have had before but this was far worse. Atypical in that there have been none of the usual obvious symptoms. Just this very ouchy deep ache on left hand side when I first sat up to get out of bed ( I did think overfull bladder!) and later when I lay down on the right hand side. Still very uncomfortable when prodded. Apart from that only a few premenstrual type cramps. No vomiting or nausea, BM's OK. However I was completely floored with utter fatigue and weakness ,dizzy, headachy total loss of appetite and interest in anything and general bhlaaaaah. I even wondered if I was having a nervous breakdown.
Maybe it is simply a ligament although getting in and out of bed is the most strenuous exercise I have had for weeks apart from simple walking, haha and I never experienced that pain again.
Anyway I felt much better yesterday and even better today although still very odd from time to time.
I have banned the word 'kidney' from my ever vigilant and fearful mind along with a few other nasty words. Thanks again - I'll let you know.
Hugs to all and thanks
Clare