Help?!

Marli

So I just fed my daughter pork chops and rice, she 2 years old going to be 3 in February. She ate the same thing last night, but this time she started to get red spots on the side of her mouth so I gave her Benadryl and stopped feeding it to her. Any idea what it could be? It happened as well like last month or two months ago, she was eating pizza from Pizza Hut and it was half pepperoni and half pepperoni with jalapeños. Hers was just the jalapeño one. My husband and I thought it was from the jalapeños but then this happened? Idk I just need some opinions on what you girls think it is?