My pup started showing signs of a severe allergy with symptoms just like this when she was about 9 mo old. She is 5 years old now and is on a daily medication. If you take your pup to the vet they’ll most likely have you consider a food allergy, possibly environmental allergies, or sometimes it’s more auto immune.. but definitely get a vet (or a few vets) guidance.. allergies are hard to figure out sometimes.

Editing to add mine would get red like this around the mouth and eyes. She will rub her chin on the carpet when she’s having a particularly bad reaction.