Your first job out of college has a high probability of being a bad fit and this is especially true if you're desperate to just get hired. So, it didn't work out... happens a lot. The important thing to do is to figure out what YOU want out of a job/workplace and to assess what that potential job can do for your career.
I think its a waste of time to try to figure out some minimal set of "red flags" to use for future interviews. Just look at the big picture, there's no single red-flag that will tell you definitively that a place is miserable (nor is there a single observation that signals an awesome place-- foozball and snacks won't make up for asshole-driven management).
Perhaps even more important than what you observe during an interview is to really examine your own needs and expectations. SOoooo many people are unhappy WHEREVER they go and always blame it on management, co-workers, the industry or whatever. This kind of serial discontent is a sign that the there's something wrong with the individual rather than their workplace(s).