I've had a P10 for almost two months now. My phone froze so I held the power button down to switch it off. It did that, but now it won't turn back on again! I have tried holding the power key and volume down key together, turning it back on, but nothing; it just shows the startup screen for about a minute then power off again. However, it has been making frequent vibrating noises every 3-8 minutes or so. I'm not sure what to do.