Is singing from the diaphragm bad? Also my vibrato comes from the throat...please tell me if it's ok! :)?

Diaphragmatic vocal support is CRUCIAL, that takes off the excess strain from the larynx that will only cause you vocal nodules, hoarseness and other nasties. Vibrato can be ONLY made PARTIALLY from the throat, usually it is one's diaphragm that is involved in this as well. In case you are a singer but do not have a proper teacher as yet, please HURRY UP and get one because face-to-face lessons are the ONLY SAFE WAY to improve one's singing without risking the vocal health too much (by learning bad habits).