Rash started around 2 any ideas?

Hi ladies,

My son started getting a rash on his chin around 2 and now its spread.

No new foods for either of us, no changes im soaps or detergents, drolling as much as normal. Not sick or acting any diffent then normal.

We did take him outside today for maybe 5 minutes since it was the first snow fall but the rash had started before then, could it have made it worse or thoughts it may be something else.

We called the pediatrician and he seemed very relaxed about it and said they would see him at 10 am tommorrow. Im just a little nervous since its on his face and now going above his top lip. Could it be a super delayed or slowest allergic reaction?