How can I get my old phone to work again?

So I dropped my phone in the toliet, about a month ago, the screen was replaced because it was cracked before and the new one was slightly out of the frame but perfectly working. But anyways, once it fell in I quickly grabbed it and dried it off. I was at school so I couldn't put it in rice but it seemed fine than about a minuet later it wouldn't turn on, or respond (no even DFU mode ) just a red dot by the frot camera area. I then (stupidly) took the screen off completely and dried off the inside (I'm sure scratching the back of the screen and the part below it (the LCD panel and digitizer I assume). Should I try to replace the screen again and see if that work or just by a new one? Also (stupid mistake again) don't trust iCloud so I didn't have anything backed up so I'm just mainly concerned if there's even a way if I can retrieve the hard drive or something.