Snoring sound while breathing in sleep.

My son is 2 and half year old...from past 3 days he is having some breathing issue...in sleep he will breathe normally for 10 mins...later on some snoring sound will come..he will swallow something and then he will sleep...when dat snoring sound comes..looks like his nose is getting blocked ...so he will wake up...he is not sleeping properly bcoz of this. Apart from this when he is awake..he is absolutely normal.. eating..playing etc and all.. no temperature..no cold..no cough also.. But i tried giving sinarest af syrup and naso clear nasal drops..no use... We are in london and here its not so easy to get an appointment...they will give appointment only fr emergency cases..we called our general practitioner.. they said some home remedies like use humidifier...hot steam and nasal drops..and said it will go on its own..but im worried.. he never did like this before.. Please let me know if this is a concern