iPhone 5s bootloop only when plugged in

My iphone 5s worked out just fine before it suddenly turned off by itself and i couldnt turn it on no matter how many times i tried. i had tried to hold down the power and home buttons together for 10 seconds, there's no result. i plugged it into the lightning device and the phone stucks in a bootloop (sometimes red screen does appear, only sometimes though and it flashes for 1 second before the screen goes black). i have never opened up my phone before to replace the screen or battery, and my phone have fallen down for a few times but those happened like months ago. Everything happened so suddenly and i dont know what to do? please help...