Default xperia v won't power on

here's what happened. i was running cm10.2 before. i was trying to clear some files thru cwm. i rebooted the phone then after that it won't power on. i already charged it overnight but it still won't power on. i already try pressing all button combinations but nothing. i also tried to flash a fresh ftf file but it isn't detecting my phone. when i charge it the red led light would stay on for maybe 5 minutes. and then it'll be off for also around 5 minutes then it will turn on again. also when i hold the power button the red led light blinks twice. i hope someone can help me with this..