Kind of redundant, but good
That was good, but I have some advice for you.
1. Try to be less redundant. It got annoying to keep hearing "think of your heart as a..." and so forth. It wasn't necessary to have things like that said so much, so, just keep the dialouge fresh.
2. As Serion said, the no eyes thing made it look un professional. Maybe once in a while if you're using them for dramatic effect, its okay. But try to put eyes in more often.
3. Nathan's voice, frankly, sounded like he was out of breath, even though he had been standing around. His speech would be like "*GASP* but what does *Gasp* this mean *gasp*" It was as if he had just ran at a track meet.
Anyways, other than that it was good.
Nice work.