Wow; how horrible, I can't even imagine

"You may wish to coach ds to learn to say directly when he doesn't feel well, if it feels like his food allergy and ask for his epi-pen in case it is needed."
this REALLY sounds like a good idea, if reasonable with a 5 yr old, but then you can't put too much of the burden on them. Ya gotta check.
I do remember when getting a recent allergy shot, turning bright red and trying to politely get the attention of the nurses who were chatting, and finally just saying "I think I'm having a reaction" which completely threw them into overdrive, so it does help to be clear whether a child or adult. (but again, kids are just not always gonna remember to be clear).