@hassanrabaa could be lots of things and we do not know until you open your phone. You must consider a damaged battery, damaged ribbon cables, damaged display and damaged circuit board as well. Since iFixit does not yet have any specific guides for this phone, use something like [https://www.youtube.com/watch?v=AHOQXszeuHg|this video] Once you have your phone disassembled, consider taking some well focused pictures and post those with your Question. That way we can see what you see and hopefully assist you further.
[guide|21499]