TL;DR: my boss is a dick and I don't know what to do.

Been working at the company for a month now, I enjoy the atmosphere and the culture (startup btw) but I really cannot stand my superior - there's only two of us in the team. Any screw up he blames it on me without a second thought. First week in he assigned their new website project to me and honestly they have quite unrealistic deadlines. I mean they didn't even have the infrastructure for it nor the manpower to build one yet it needs to be finished by the end of this month. On top of that the spec keeps changing literally every 2-3 hours.

Also since I've forgotten to mention the guy I'm working under is one of the founders so I can't really go and talk to someone about it. I feel pretty screwed over, anyone has any advice or been in a situation like this? Is it too early to quit?