Hi there ~
I understand your concerns. I believe that your son has been suffering from a viral infection and your description of hives
does not seem like an allergic reaction
. You should consult a pediatrician
or a dermatologist
so as to know what kind of lesions they are and get the right treatment for them. In the meantime, use adequate hydration as well as rest and sleep for your baby to make him feel better sooner.
I hope this helps. Take care! Have a lovely day!