is his cough dry or is it productive? if productive is the phlegm greenish and thick? if it is then that would indicate a bacterial infection which would respond to antibiotics.
if the cough is dry or phlegm is clear then it indicates viral so antibiotics no use.
gp's listening to chests is accurate enough to see if it's clear. if there isn't obstruction or thick mucus breath sounds are easy to hear right down to the bases of the lungs. pneumonia normally blocks these breath sounds down in the lower lobes of the lungs as gravity will settle the mucus there and it's harder to cough up as it is thick.
with both viral and bacterial respiratory problems wheezing is common when listening to chest, so the main difference is the quality of breath sounds and the locations of them. duller sounds or absence of sounds in some areas with bacterial.
treat the pain and the temperature with medication. plenty of fluids to prevent dehydration as this will thicken any mucus secretions and make it more difficult and painful to cough up.
a good regime for medication is to start with a full dose of ibuprofen first, two reasons 1. it is a really effective medication for temperatures, 2. the anti-inflammatory properties help if there is any irritation in the throat. if your son is off his food then cold milk is good enough to protect his stomach. it is also the linger acting medication so can't be given again for 6-8 hours and not more than 3 times in 24 hours.
if in 2-3 hours you notice his temperature is creeping back up then give half a dose of paracetamol. only half a dose so that you still have another dose 2-3 hours later if pain/temperature creeps up again.
you'll then find 2-3 hours after this you can re-dose with ibuprofen and then repeat throughout day to give a really constant release of pain relief instead of peaks and troughs.
example: total
6am ibuprofen full dose. 1 full ibuprofen
8-9am paracetamol half dose.
11-12 paracetamol half dose. 1 full ibuprofen & 1 full paracetamol
2-3 full ibuprofen 2 fill ibuprof. 1 full paracet.
4-6 half paracetamol
8-9pm half paracet. 2 full ibufrof 2 full paracet.
if this works throughout the day it will leave 1 full ibuprofen for during the night or a bedtime dose, and 2 full paracetamol doses to use either in halves or full doses depending on how many time he's waking up. so no chance of overdosing 3 ibuprofen in 24 hours and 4 paracetamol in 24 hours. it is worht keeping a record of times for your doses until you get used to split dose regimes.
sorry if i've waffled/patronised in anyway, just wanted to be clear when it comes to medication. also i've been lazy and not used capitals, please forgive and all the best.