Newborn fever

How long should a newborn (2months) have a fever for?

My baby has had a fever on and off low grade for 8 days now. His pediatrician checked him out on Monday he said to give him children’s Tylenol. I did for the first two days but stopped bc the box said to check with the doctor if it continued more then two days. I’ve spoke with the pediatrician several times since and he said he most likely has a virus and as long as he’s otherwise fine not to worry his body will fight it out naturally. His lymph nodes are swollen and his fever ranges from 99.5- 101.5.

His doctor doesn’t see concerned, I know his fever is on and off low grade but it’s still a fever. He’s so young and I’m just wondering how long were supposed to let this last for?

Anyone have any experience is this department?