From your symptoms it appears like you are having Reflux which aggravates at night. It is usually presents as a small phlegm in the throat and makes u cough
at night. If you are not having any other symptoms then this is most likely the cause.
I would advise you
-to take reflux medication
-drink plenty of water
-take less spicy food and less oil.
If these measure do not make u better then visit an ENT specialist
I hope you found my response to be helpful and informative. If you have any additional concerns I would be happy to address them.