Is my snowboard way too long?

So, I have a 155cm snowboard which I've been using ever since I started snowboarding, so I'm completely used to it. I've just started to try jumping and stuff in the terrain park. I'm 5'9" and I'm 120 pounds, so I'm guessing it's way too long for me. Does this make a whole lot of difference? Is it bad that it's so long?