If you confirmed the connections are seated and there is no physical damage that you can spot, odds are you most likely damaged the LCD. As far as the home button goes, that could be damaged as well. Typically I see that specific issue after the screen has been replaced and is usually caused either when the bracket for the home button doesn’t quite line up right or the little button that clicks when you press it becomes damaged. That can be repaired by a skilled micro soldering tech but if you just want to restore the function to return home and multitask, just order a replacement button along with a new screen. Just be aware that by replacing the button, you will permanently lose touch ID unless you use the original one. The original home buttons with TouchID are paired to each board. The only way to maintain it is to use a special tool that only apple has.