Acer Aspire E5-575G-7211 screen won't light up

My laptop was still working fine 3 hours ago. I was going to replace its thermal paste and the teardown went well until I got to removing the heatsink. The screws were practically immovable so I gave up. I assembled everything and booted it up. It showed the Acer logo and was stuck with it. for some time but I figured that's normal. After some time, the screen just went off but the lights indicating it was plugged in and turned on were still lit up. I tried reopening it again to see if I had forgotten anything vital at all and it seems I didn't so I sealed it off again and turned it on, this time draining the battery. Now, I drained the battery and turned it on once the light had gone off to ensure that there was no battery left. I plugged it in and pressed the power button and it has been like this for the past 30 minutes or so. Really hoping to shed some light on this issue, thanks in advance!