Wow...this is really dark and you were fighting some serious contrast. It looks like you went with your camera's default metering - sometimes, with difficult shots like this, it's a good idea to bracket your shots. If you don't know what bracketing is, it's shooting (generally) 3 shots, one at what you think the exposure should be and one over and one under exposed from that. You get a much better chance of getting a usably exposed shot that way.