At my breaking point

I'm just so frustrated right now that I'm in tears. My son is two weeks old, and the first week of breast feeding went perfectly. He'd eat on both sides for about 15 minutes, I'd burp him in between, rock him back to sleep, and he'd wake me in 2-3 hours wanting fed again. This week has been a nightmare. He cries wanting fed all the time. Which would be okay, but nearly half the time he projectile vomits all he's eaten. And the cycle starts again. I've cut down his feeding times (thinking I'm overfeeding), I burp him during each breast and in between, I keep him elevated a half hour after every feeding, and I've also tried gripe water. Nothing works. I'm constantly cleaning up puke and dealing with a hungry, crying baby. I feel like a failure for not being able to give him what he needs. I'm just hoping I don't have to go to formula. Any advice?