Alright guys, now we can't just "assume" it's something without a test. I would strongly encourage to take the unit to a board specialist to test the board to determine which component may be compromised, or having an minor breakdown.
Update* (because apparently I was AFK for too long)
It's awesome your device is working again! To prevent losing data, I would strongly encourage to keep a back up of device, especially if you have some important data in it. Make sure to keep your back up active on Icloud and/or set up your main PC to auto sync over the wi-fi. Here is an article for[https://support.apple.com/en-us/ht203075|Sync over Wifi]