11 month old puppy has welts/hives/bumps all over her body and legs.. not sure if it’s from something she ate, bees, allergic reaction to some type of plant? She’s acting pretty normal otherwise, just looks terrible! Her vet doesn’t have any appointments available for 10 days. He did say to give her Benadryl, which she has had two doses of and doesn’t seem to be helping much. When should I worry and consider taking her to an emergency vet clinic?