Tired Phoebe

I have been a bit concerned about Phoebe today, she seems to have even less energy. Phoebe has been eating ok today, so I guess this is a positive sign. However she seems to be very lethargic today and her heart seems to be racing. This is perhaps just paranoia, but I cannot help worrying. I am taking her to the vets first thing tomorrow morning, so hopefully we will no more then.