Awesome
This song was really cool, I really got into it. Can't believe it's your first.
Try mixing up the guitar a little bit, just adding some effects into the mix. For most of the the songs I like I feel the melody (guitar) should always be changing or it sounds kinda repetitive. This song had that repetitive feel but I really think just little effects (like distortion as F-777 suggested) can make the song that much better.
Great job!