Does my son has Acid Reflux?

My son is 2 years old. In recent 3 weeks, he wakes up at between 1:00am and 2:00am every night due to coughing caused by phlegm in his throat.  Meanwhile, he is also very fussy and wants me hold him in up position.  I can see he was trying to swallow something coming from his stomach.  Sometimes I even can feel that there is a pressure up and down in his tummy.  If this pressure flow is strong, he will vomit even though he tried his best to control it.  After vomiting, he normally feel much better and can go back to sleep. 

In the day time, he is normally doing OK except occasional nausea.  Other information is:  He is normally a light eater.  He recently goes to daycare and doesn't eat well at daycare.  So he has a very big dinner at home (around 7:00pm).  And somehow, he doesn't like breakfast.  That means he takes almost all the food just at dinner time.  He just has no interest with the food and said he is not hungry.

Does my son has acid reflux problem and if he needs treatment?

Thanks a lot.

A worried mother