It sounds like your dock (or iPhone) keeps losing connection to the other and then reconnecting. That would be why iPhoto keeps opening up, since it will open whenever you plug in your iPhone.
My iPhone makes a noise (not sure if it vibrates) when a sync starts, so if it keeps reconnecting to the dock and starts syncing again, maybe that's what the constant vibration is.
Try it with the regular iPhone/iPod cable and see if it does the same thing. If so, it's probably your phone, if not then it's probably your dock.