iphone 6 blue screen of death

i have an iphone 6 16gb, iOS 8.4 that i got in May and it has been going crazy! it'll randomly turn on and off and flash a blue screen. this will last for about 3-4 hours at a time and the phone gets really hot. i have to hold down the lock and home button in order to get it to cut off completely. has anyone else had this problem?! so weird 😕