Ok, Jay, I have listened to your the music on your link and as a classical singer I am no metal expert, but I'd give you the following advice:
for starters, don't put yourself down! Positive attitude and belief in yourself is everything. Consider this: if you don't believe in what you do, then how could your audience?
Secondly, the main thing that you need to take care of is your voice, and that means improving your vocal technique and muscle support. You mention that your throat feels tight after singing. This indicates that you are tensing up in the wrong places, which will probably kill your voice in the long run if you continue doing this.
As for remedies, first of all read up on all the exercises and hints and tips found on the vocalist main site. It's a great starting point. However, I would always advise anyone to seek the opinion of a professional vocal coach as it is nearly impossible to give proper advice without seeing and hearing you sing. I know that this is an expensive thing to do, but I would look at it as an investment. After all, if you are a singer then your voice is your tool. It's an expensive tool because you can't replace it once it's gone. Best take care of it, eh?
Good luck!