You have been told that you are suffering from Viral infection. You are taking pain killers and antihistamines for the last 3 days. Since yesterday a rash
appeared initially in your palm has spread to most of your body, your ankles are swollen and you have stiffness
in your lower limbs
. I don't know which country you are living, because certain lesions are not prevalent in few countries.
Even though an allergic etiology is the first diagnosis for sudden onset of rashes all over the body, the way you have presented your symptoms go in favor of measles
and then Small pox. Consult a dermatologist
and Physician to rule out these and take proper treatment.