Thank you all.
No not cystitus but has had an on off upset tummy which responds very well and quickly to probiotics......must order some more.
It suddenly reappeared just before she started lying in one of the trays and it did go very cold last night and this tray by a radiator.
She has been indoors soley now for 3-4 weeks but is staying upstairs and not seemingly wanting to go out at all.
I dont want to take her to the vets unless absolutely essential as it will mean trapping her in the house and very stressful for all.
I have only been able to stroke her for the last 3 weeks after nearly 7 years and am just building up a little bit of trust although she is terrified of feet. She is a semi feral calico tortie who started living outside about 6 months ago until she only came inside for a quick feed and left again.