My 6 mo old started throwing up 2-3x/day for about a week & now isn't sleeping well. Could he be teething? He goes for shots the 13th.

Call your doctor. Fussiness and trouble sleeping can be caused by teething. Throwing up is not. Please contact your doctor. Hope your little one feels better soon.
No, Definitely Not. He needs to be examined by his physician. Teething does not cause vomiting, and although he may be teething, he has something else going on as well.
Not from teething. Make sure to keep your child hydrated, and call your pediatrician. Pediatrician may want to see your child before the 13th.