Allergies! Huge scare! Advice?

Tesia

Hello. I'm a mother of 3 handsome young boys with another coming soon. I just wanted to ask and hear other parents opinions/experiences.

My youngest is 13 months, he is still breastfeeding but is mostly on solid everyday food. Has been since around 7 months never had an issue or scare.

About 3 days ago he developed hives that started on the back of his neck, his lower back, chest and under arms. I instantly freaked out and called his pediatrician. She seen him via virtual appointment told me since he wasn't coughing, vomiting and that it wasn't really bothering him just to give him so benadryl and see how it goes.

It never fully went away that night but the hives did go down and looked more like a red rash covering his body. Next day the rash started to migrate around his body his face began to swell up so I took him to the ER.

They didn't seem to concerned since he was breathing fine and it wasn't really bothering him. Just gave us steroids and sent us home.

I'm still freaking out, I've never dealt with allergies/hives. How can I tell if it was from food?(He hasn't had anything new.) I haven't changed any laundry detergent, soaps, cleaning products etc. Has this happened to anyone else? His breathing hasnt been an issue. I just want some type of peace of mind.

The hives come and go now. Once the benadryl wears off it comes back sometimes bad others mild. I just dont understand what it is. Help.