Hi there,
Is the runny nose the only issue? My DD2 gets a clear runny nose when she is exposed to an allergen, however it is always accompanied by runny, mucousy stools, rashes, etc.
There can be many different symptoms - ranging from runny noses, to hives/rashes/excema, constipation or loose stools, muscousy stools, blood in stool, to name a few.
Honestly if it's *just* a runny nose I would not think food allergy - perhaps an environmental issue, or something else.
((hugs)) - hope it's nothing, but maybe put a call into your dr for peace of mind.
HTH!
-Tari