I had lost my AC plug, I took it to Radio Shack & bought another, it worked. I then tried to charge the battery. The 'charge' light would not come on. Does it come on red & then turn green when charged, or come on when charged? Also now, This morning it will not come on at all. Did I do something wrong to charge it? What is the procedure for charging? Will it damage the machine if I had put the AC plug into the DC plug hole by mistake but the machine was off.?