Honestly I would turn it off and charge I think you would see better results, and just leave it alone until it gets to 100%.
This is the official OTA update, no root and all stock with the exception of some apps. I guess it could be possible that the battery just took a dump but if that is the case it is real odd that it happened as soon as the update came. Tonight before I go to bed I am going to turn the phone off and let it charge all night. I really hope that the Android battery meter isnt wrong and the phone is actually overcharging the battery. The back cover does feel a bit warm.
Raydee, go into setting, and battery info, and get us a screenshot... you do that by holding power and volume down. Perhaps it will help us to help you
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