Well today I charged it and it was working I used it for a few then I turned it off and put it back on the charger and then it was off the charger for a few then I went to turn it on and now its not turning on at all like it lost its charge....did I over charge it is it broken ? Usually it gets hot when charged and warm when a few minutes into charging but it has been charging for 20 minutes and hasn't got hot it wont even turn on its a bioteck ex-02s