Thanks for your query.
Your history suggest an allergic reaction
. Maybe he ate something that he shouldn't? Anyway, if he is feeling well, breathing well and does not have an upset stomach anymore, you could try benadryl
or other anti-allergic medication that he has used in the past. Use the smallest dose recommended in the instructions and observe him. If you don't see an improvement, consult with a pediatrician
Have a nice day, and good luck.