Note 5 had a blue blinking light now just red

[AC Question]

Hey! So I've had my Note 5 for a while now and never had any problems with it. This after noon after it died I put it on the charging dock. When it reached 35% I tried to turn it on as I normally do but it wouldn't start. I put it back on the dock and the dreaded blue light appeared. I also noticed it was super hot! I tried rebooting multiple times but to no avail. I gave up and put it back on the dock as one poster on another thread suggested leaving it to charge for multiple hours. Now the blue blinking light has turned into just a red light. & also if I unplug the phone from the charger the light turns off. Any ideas?