Coolmommy, this was great to read because this fire is something that is so rare in the church.
First of all, none of us are worthy of salvation. That's the truth, and this may very be the catalyst for your desire to serve the Lord. Remember it was the publican not the Pharisee that got saved in Jesus' parablle. Read Luke 18:10-14 for a encouragement and refreshment.
Regarding the fire, this is great. Feed it, read, sing, do whatever, and remember the devil will see you as a threat. We all know he tries to get us to sin, and that's one part of spiritual warfare, but what most people forget is that devil is also an accuser of the brethren. That is his name, in fact; satan means accuser. So he will try to dampen your fire and wear out your enthusiansm by accusing you at every turn. Now he wants to accuse you of pride by making you feel you cannot enjoy the encouragement others give you. Since you've already said you feel unworthy, you are not a prideful person. As long as you remember Who you're singing for and Who gave you the talent, why not enjoy the encouragement? Sometimes you'll need to know that you're making a difference for the Lord and that people are being edified by your talents. Enjoy it. Just might want to keep an eye out, because if the devil can't wear you out by falsely accusing you, finding ways to induce sin will be his next step.

Blessings to you!