Laptop Wont Turn On but power button keeps blinking white

[MO-5549]

hi i have a toshiba satellite L50-c1709
last night i noticed it getting hot over normal programes not modelling/ gaming
i opened its back cleared the old thermal paste and replaced with a newer cooler master and also cleaned the fan
after putting it back together it wouldnt turn on there is a led circle around the power button the keeps blinking continuously as i hold the power button
the battery led was orange while charging and now white as its charged (thats its normal lights)
I've tried taking off battery & charger ->holding power button for 30 secs then powering again but it doesnt work
PLEASE I REALLY NEED URGENT HELP AS I USE THIS LAPTOP FOR ALL MY MODELLING WORK AT SCHOOL & WORK

 

[MO-5549]

Minor Update
while holding the power button the led around it blinks short blinks for 10 secs then stops for 1-2 secs then blinks 2 more times then stops