Hello, I just picked up this phone. Really liked it but I have a small issue. Most of the time I press the "back" button or type on the keyboard I feel a vibration as is the hard drive is doing it. Is this supposed to be normal? or is it something I should return the phone to the store and have replaced for? Feels like an old hard drive vibrating when it's about to die. Maybe I'm mistaking this for some other feature in the phone where it vibrates every time I do something. Thanks! ps. my other phone has notifications (ie. missed calls etc.) on the lock screen and I can't seem to figure out how to get that on android. Is this something that is not built into the OS? I would love to have like a pop-up or a list of missed calls, etc. on the home without having to pull down the notification thing. ty again.