as long as she wants her milk then I would just continue feeding her milk - it should only be a phase and will get over it soon. try not to worry too much - she should be fine as long as she enjoys eating (drinking) her milk!
My daughter started eating again after 4 days of no eating. So don't worry! As for the fever and heat rash that may be what is causing her to not eat. Give her medicine to lower the fever and calamine lotion for the heat rash.