I recently got over pneumonia 3 weeks ago I have had the sharp pains in my chest for over a month I went to the ER on Saturday they gave me pain meds but ever since I've been home I have been throwing up and the chest pains are more severe I have not been able to eat for 3 days because nothing will stay down

Too many questions! We don't know that you got over it. We don't know if you had any tests when you went back. We don't know if you can't tolerate certain painkillers (anything starting with Perco- makes me vomit).
It does sound like the pneumonia is still there.
Go back to a daytime walk in clinic if you can, not an ER! Much better care for something like this.