Phone will not turn on after screen replacement

I went to replace my screen and now my phone won't turn on at all. I put the clasps back on and turned my phone on to see if it would work and it did. I then put the screws in and tried turning it back on and nothing. I went to unscrew them again because I thought maybe one of the clasps came undone and while I was unscrewing one of them the screen turned on temporarily. I am fairly certain I did not put the long screw in the wrong hole but after searching the internet that is the only reason I can come up with since nothing else has worked. Again I don't think LSD is the case but if it is is there anyway to repair that either my self or at a phone repair shop or is there anything else that might be causing this?