What do you think of my singing?

gotta hand it to you, you did quite well. I don't listen much to Green Day, but I have listened to them enough to see you have some Billy Joe Armstrong influences in your singing :) I agree with the person that said on your video "you should learn guitar and it'd be great". Keep it up, and I know how it goes with the nerves (I'm confident w/ my voice but I sometimes get nervous around my family) but try to keep calm, relaxed and confident. You've got nothing to worry about, except that you sing the song from your soul. Also, the people above are correct about adding more emotion from the diaphragm. I know it's hard to do - I still can't quite get the hang of it every time, but it does help a lot when it happens.