Screen remains dark screen after switching power on

Hello, first i start by saying i may not be having so much idea about computers but i need some help please.Yesterday i changed my personal computer(PC) from windows 8 to windows 10 after installing and everything was well i used my pc comfortably.Today in the morning switched on the computer as usual once i logged in,a flash message on top on the screen appeared indicating that my PC got some error it needs restarting will do it for you then i started running from 0% once it reached 70% the laptop switched off then the power button started blinking blinking for like 5-8minutes finally it behaved in the manner of switching on bt the screen is not responding its just dark just as the way it appears when its off up to now its just like that but the computer is on.Three days later before i installed windows 10 it has been having the same problem of indicating that my PC has an error it needs restarting til after installing windows 10 it stopped working in that when i switch on the power button it responds bt the screen remains dark screen no response.please help me out what might b the problem?