Has anyone's toddlers had a rash like this? It's red with very small bumps and it's spreading quite alot but doesn't seem to be bothering my son at all. He's booked in to the doctors in the morning as that's the soonest I could get him in but i took him to show a pharmacist while I'm waiting to see the dr and he said it looked like a type of nappy rash/dermatitis but I'm not convinced due to how much it has spread.

I also haven't given him any new food or changed washing powders/soaps etc.