See if the bracket at the back of the ear speaker it clips in securely, if is not, that bracket may touch something that will short. Aftermarket screens are not 100% same as originals, so the plastic bit were the the clip of the bracket needs to go, may be a little to big. It happened to me when i was replacing the screen on my daughter's iPhone 5s. After cleaning the plastic edge where the clip goes in to and applying a bit of pressure on the bracket it clipped. Then i put everything back together and it worked. I hope this works for you, or for other people who has same issue.