So, I got into to work today and to my horror my scooby's dial was on H.. right at the top!
I went out in her at lunch and it is doing the same after around 5/7 miles.

I topped up the oil the other night and shes been fine up until today so iam not sure weather to just top up the radiator with water so i can get home or go to halfords and buy some coolant but iam not sure of the coolant that is in it? any ideas?

Not sure if it helps but i have been doing around 70 miles a day in it over the last week and a half because of training.. totally gutted because i didnt want to use it for that but i have no choice!