if you click the i at the bottom right corner it should display serial and imei number, if there is no imei then it will need a new Baseband chip (i think).
if the homebutton is super sensitive then its usually the flex on the actual homebutton that is damaged.(usually from opening the phone wrong). Also check the flex on the screen, its the smaller connector that is responsible for the home button and is easily ripped where it bends through 180deg.