 [ Symptoms ] i noticed a burning sensation on my side the redness spread and turned redpurple and still spreading [ Disease ] first possibility is lyme disease as u discribed it started by red pump look for signs as headache and fever use doxycycline if non then it could be hiv infection which can lead to aids usually body can fight it alone but take it seriously my assumptions are based on posdiblity that you had a mosquito bite or some insect bite could be just contact dermatitis if your sure you have not been bitten by any insect also look for sore throat and fever if non you are safe