air sound after oil change

[Nibs]

hey guys just changed my oil to Royal Purple after hearing such god things about it.

So I started the engine up after the change and after a couple minutes I hit the gas just a little and noticed a weird sound. Its like air pushing or something just as you hit the gas pedal. Almost sounds like a squeek?very fast and brief noise. I've never noticed this sound before and am now just paranoid somethings wrong after I changed the oil. No idea what I could have done wrong.....

has this always been there and am I just hearing it for the first time...