Dropped phone won't start up, only flashes when charging

I dropped my phone a couple days ago, it turned off and then didn't turn back on and I just thought I had to charge it back up and then it would be working fine again because I've dropped it and had it shut off for a second before. Since I dropped it, it doesn't turn on or flash or anything at all when it's not plugged in, but when I do plug it in it just flashes the powered by Android logo screen and stays in a loop. I've tried holding down the vol down button and power button but that just makes it go to the screen that says to press volume up for download a custom os, volume down to cancel (restart phone), but when I restart it just goes back into a loop and when I choose continue it says it's downloading but it doesn't actually seem to be doing anything.