Hi!my Son Is 15 Month So Old And I Came

Hi!my son is 15 month so old and I came to visit my parents out of the USA.my son was on fresh milk but due to travellong Imy giving him nido.I found rashes on his whole body and these rashes are like red bumps but not itchy.and theyes are getting bigger in size.it's my idea that he has rashes due to nido Milk.I'm really worried.kindly help me out.
Regards