I replaced my iPhone screen and it will not come back on, what else could be wrong with it?

I replaced my iPhone screen and at first it was working fine but one if the connectors (the smaller one) kept coming lose and would not stay in place, I kept trying to make it connect and the spot where they clip together started smoking a little, I exchanged the screen and when i put the new screen on it just showed the Apple logo, I put another screen on and now it will not come on at all, I don’t even think it will charge and the back light doesn’t come on either, is thier a way to fix this?