I used Suzanne from the nanny agency Nick has mentioned for my latest nanny who has been with us for over 2 years now. She partners with another agency in Woking, so there is a wider pool of people to access. Godalming (I'm in Milford) proved to be no problem.
Do you have other friends with nannies who might know of someone who could help. I can always ask around here if there's someone our local nannies know who might be between jobs currently, if you could provide a few details....whilst not revealing yourself of course!
Nannies often work through illness (probably a bad habit but we don't like letting our employers down), so she may well be very ill, or there may be some kind of issue... which you may be picking up on if you have a "bad feeling".