This is a really nice shot. I tend to be drawn to your darker, more eerie photographs for what ever reason. I love your brighter landscape photographs as well, You just have a good eye for capturing the gaze quality in photographs like this. I hope I am making sense here..
As far as tips, I'm not a photographer so I won't even pretend to know where to start with giving you any. You mention underexposed, and I believe I can see what you mean, but then again, one would really need to have some high standards to critique this in a derogatory manner. That's just futuremind's humble opinion, for what ever it's worth. Much love!