Allergy?

I thought little Paxton would be able to tolerate milk since he is now 10 months old so last night I tested my theory and gave three ounces of milk mixed with formula before he went to sleep. As it turns out, Paxton is definitely allergic, which is weird cause he has eaten yogurt and ice cream with no such reaction. This morning when he woke up I got him out of bed and took off his pajamas to discover this....
Hives from head to toe! Poor little guy. He is allergic to bananas and the whole wheat cereal too, but never had a reaction like this! I will definitely not be giving him peanut butter any time soon and when I do, I'll be parked in the hospital parking lot in case he goes into anaphylaxis! (thanks for that idea Becky) It's just one thing after the next with this kid!