I think i broke my iphone 4?

I tried to install a new glass screen on my iphone. By doing so, i unscrewed some screws and when i put them all back together, the display won't work. Like the screen is completely black. The phone still rings when i get a text or call but i can't see what i'm doing on the screen because it won't turn on.

You need to call your phone carrier. To remove the glass a phone company has to do that.

By saying install a new glass screen, did you break it? You install just the digitizer touch panel? Including the LCD display or not? Cuz if you see nothing on the screen, it is the problem with the LCD display. It might be broken or not connect well. Some info for separated parts and assembled parts for your reference.