Well...
First off... You should be happy with what you have. You sounded awsome. Lol, you think your mic sucks... My mic sucks. Check out my song "He Isn't Right"!
Anyways, love the changes you made in the melody, and your unique harmony. Lovely piano, and everything seemed to fit well... Overall... I thought this was a good cover. Keep up the good work, and moving your fans. I hope to hear more of your songs.