My phone died last night, I charged it this morning and rebooted.. Now all day I've had pretty bad lag. It's been pretty inconsistent, it will lag for a while then it seems to run fine for a while. It got so bad at one point that sense actually forced closed itself then re loaded. I ran a quadrant test just to see and my score went from in 1500's last week to around 900 today... Something just isn't right. Should I just take the phone back to best buy or is there something I can do to get it running smoothly again?