My brake pedal is making an airy noise, like deflating a ball every time i press it. What is it? Is it something i should be concerned about? Thanks...

 

If it's a hissing or almost a whooshing sound from under the dash, it may be the booster. That's a tell-tale sign of a failed one. You should get it checked out one way or another. Any brake related problem is never one to ignore.