Fever

My son has never really gotten sick occasional cold with like 99/100 temp but never as bad as today. He woke up today with a temp of 101.4 I let him eat breakfast he was miserable and I have to add also constipated. Took an early nap 10:30-12:45 and woke up with 102.2 that’s when I gave medicine. Miserable again just wanted to be held no matter what. We normally do a nap 11:30/12-2:00 and bedtime at 8. Today he took another nap at 4:30 which I normally wouldn’t let him Bc he’s will sleep til 6 if you let him and the bedtime is horrible. But now he’s finally back to sleep and at 102 temp again :( when should I contact his doctor? I was told by a friend 48 hours if the fever has not broke to go in and get him checked. Just wanted to see what other mamas do. I just never really went through this with him yet and I’m lost.

I would like to add he isn’t really coughing or anything either. Just the fever so far.