Replaced the screen and now my surface pro 7 won’t turn on?

So I decided to finally change out the screen on my old pro 7 that’s been cracked since day 2. The damage was the speakers and screen, which I repaired both rather easily. I connected it up to test if the screen worked, and it booted just fine. I decided to detach the screen, p(and battery), apply the adhesive, reattach the screen and test it one last time to make sure it the speakers and touch worked before I sealed it.

But it won’t even turn on. No heat, nothing. I’m so angry it’s fan less because there is no way to tell if it’s the wonky computer or the screen. The old screen does the same thing when it’s plugged back in.

I don’t understand it. is there something I could have somehow shorted between putting the adhesive on and the screen back in? What’s the red light on the motherboard mean? Or is it always there? It was there when i tested it the first time and it worked. No external display works either, but the surface charger lights up when plugged in. Im out of ideas on what could have happened unless someone somehow spilled water on it without me looking.