Tried to fix camera- home button broke and now screen won't turn on

Hi, I tried to fix my shaky camera by putting a little magnet on it. I took the camera out first to check it. When I turned on the phone to check if the camera shaking stopped, it said touch ID unavailable. I put everything back in its place, turned the phone on again, and now the home button isn't working at all. I use my computer to return to factory settings, and when it turned back on the screen brightness was extremely low. Now I can't see anything on the screen. I've tried to detach and reattach everything, and I don't see any tears on the home button flex cable. What could possibly be wrong? My phone is a refurbished one if that matters.