I second the Martial Arts suggestion. Today was my first day out and I fell........many times. I fell forward.....I fell backwards......I even manage to twist and fall. I had the similar experience you are describing. I could stand on the board a get great speed on the bunny hill, but when it came time to stop....look out! I feel fine right now, because MA teaches you how to fall, when being thrown (well at least Aikido & Judo). I had people come up and ask if I was ok because it looked horrible. But I was fine.
I am a big supplement person and I learned years ago Shark Cartilage will be your friend. SC increases blood flow to the vascular tissues. Shark Cartilage will take away the bruising and if used regularly you probably will never bruise or if you do it will be small and quick to leave. Make sure it is freeze dried. I have been punched and kicked in the face so many times over the past 24 years in training & competition and only have had 2 to 3 black eyes because of this.
Don't give up. I had the same experience you did and will be out again this week.