Red Itchy Eyes

My 2 yo has been having itchy red eyes for 5 days eversince. So far no pus. Brought him to see his PD and was prescribed with 2 types of eye drops and a running nose meds to help reduce the itch. Been 2 days now and the redness still there. After applying the eye drops, the redness will go away but after 2 hours or more the redness will come back. PD said it's not conjunctivitis. Should I be worried? Anyone faced this before with your lo?