Your son needs examination by a paediatrician and an ENT surgeon. The vomiting may be due to gastritis (acidity) due to the medicines, especially if you have been giving them on an empty stomach. There is a rare chance of the vomiting being due to the ear infection, especially if it is projectile. Very young children can easily get dehydrated and continuous vomiting & ORS use can cause electrolyte disturbances. Anti-emetic (anti-vomiting) medicines (drops / syrups) like Reglan / Ondem/ Emset may be required to control severe vomiting.

Please be extra careful and take an immediate opinion if he looks pale and is weak / lethargic/ not responding well, has a dry tongue or decreased skin turgor (elasticity), has increasing ear pain or headache,

Get a proper consultation by a  experienced pediatrician done. He will need medicines to stop his puking along with the other medicines for ear infection. give him small sips of ORS solution. It will help for his tiredness.