When I sleep, I keep my phone under my pillow charging. I had a charger that would charge the phone, but while I'm sleeping (or any time it is charging), it would constantly vibrate because it would stop charging momentarily as if I had unplugged it. (The phone gives off a short vibration spurt when you plug in the charger) Thinking it was the charger, I bought a new USB plug so I could plug it into the electrical outlet thing. This charger did the same thing. I am using a different charger now, and it is still happening. Do I need to replace my phone?