Maybe your baby is not feeling uncomfortable? Something must have made him uncomfortable that he reacts that way.
Stomach bloated etc?
I read Ruyi oil has 2 types, they have one special for baby.
The normal one is too hot for baby's gentle skin. Do you get the right one?
Do you have air filter at the nursery or the room where your babies sleep?
I have air filter, and I believe that helps to keep the air in the room cleaner, hence my baby seldom have blocked nose problem, phlegm or cough.
Baby's respiratory system is still very weak, cleaner air surely helps them to stay away from illness.
If baby prefers certain position for feeding, just follow their lead.
Maybe you can find a way to have a mirror in front of you so you can see your baby?
once you have 'mastered' this position, you may do away without the mirror.
As for refusing or drink lesser than usual, not too worry.
My baby once in awhile will do that, totally refused to drink or drank very little, for few days.
but after that period past, he was back to his normal routine.
Hope this helps.