Red/purple rash on foot on holiday, not itchy but very tingly, rash has burning sensation in sun, entire foot swelling to large size nochange in4 days?

Med eval. This can't be diagnosed with the information that is available. A history, physical examination & other studies may be needed to determine cause/causes. Once accurately assessed a treatment plan can be developed.
Skip the Flannel. Sounds like you came in contact with more than you bargained while on holiday. You best bet is to have it evaluated by a doctor, before potential tissue break down begins.