GS4

Well i just finished installing my system when I closed my hood and started driving away and I see smoke coming from under the hood. I opened the hood and saw that the positive battery cover was on fire. The battery terminal that i had installed had made contact with the hood. There is a slight humming noise coming from the engine bay when I rev up the engine now. Does anyone know what I could have damaged from doing this? Also what could I do to correct this problem? Could my amps have been affected?
Thanks
GS4