Why would i only get pain on my outside of my ankles after hockey?

Two possibilities: One is that your skates do not fit correctly. Another is the muscles that you use when skating. When pushing to the outside you fire the peroneal muscles. The tendons of these muscles run on the outside of your ankles.

Peroneal tendinitis.: Pain on the outside of your ankles could be several different things, but the two most common are ligament tears (similar to a mild sprained ankle), or peroneal tendinitis. Your peroneal tendons help stabilize your foot on uneven terrain, and they may be irritated by having to balance on a thin skate during hockey.