I have to agree with crambone. Did you have an ultrasound of your gallbladder when you were in the ER? Pain in the stomach and into the back, along with vomiting bile sounds like you are having a pancreatitis attack. If it's not your gallbladder, it could be that your bile duct is not draining properly. Many years ago I had the same problem. Gallbladder was normal and they ended up doing exploratory surgery. Bile duct was not draining and a sphincterotomy was done. I've had 3 more of these since and have since develped pancreatitis. If the ER did not do an ultrasound of the gallbladder, have your family physician order it. If this is normal, you need to see a gastroenterologist.
Good Luck.
I've brought that up before the the ER doctors and they said that wasn't the problem. :-/
pancreas issues,,,possible gallbladder problems,usualy the green bile though is from too much in the stomach,and an empty stomach,,kinda like dry heaves they call that,if there was food,you would vomit food.
im thinking gallbaldder