Youth plus "newbie" equals the person likely to fall victim to office hearsay. Once you land a job, resist the urge to believe what other co-workers tell you about your boss, that one lady that sits in the corner or even how to handle certain situations with clients.
Some of the veterans in the office will look to mentor you and help you thrive, but never assume that others won't consider you a threat. Remember to trust your instincts.
If you believe that you have a creative idea or an important message to tell your boss, select an appropriate time and tell her or him. Don't fall victim to the ever famous, "Well, John said he doesn't like to be bothered with that sort of thing, so I didn't speak up." Perhaps John does not have a unique idea nor the ability to confidently articulate an idea. Ever consider that? Seems harsh, but true.
If your boss truly does not want to be bothered with certain ideas or messages, let your boss express that to you personally. Never assume and never trust that everyone in the office wants to see you shine. The unfortunate reality is, some do and others would like to start-up a petition in favor of your forced resignation. Be optimistic, but also a realist.