hi welcome to HCM
i had gone through your query and understand your concerns.
basing on your complaints,i would come up with two possibilities.
1.the first one is-fungal infection
likely RINGWORM;local examination may confirm the diagnosis
2.the second one is ALLERGY
may be the cause.
-food and food additives
-Drugs are some predisposing factors.
I hope this is helpful for you, thank you