Replacement screen won’t turn on, keeps rebooting but no luck

Hi,

I recently replaced my MacBook Pro 13.3 inch screen. After the replacement the screen would not turn on. I tried everything there is to reboot the computer but the screen is still not working. The touchpad is lighting up and I can hear the charging sound as well as the sound MacBooks makes when they’re starting back up but the screen will not power on. Also I have to connect the MacBook to its charger otherwise it won’t turn on. It feels like the computer is stuck on sleep mode because I have tried to force shutdown through shortcuts on the keyboard but it turns back on easily when I press any key. Is there anyway I can know for sure if it’s the screen intself or if my MacBook is damaged for good?