Help with Dome Light

Hey guys, how's everyone doing? Been awhile since I've posted anything here, Stangs been treating me good , till now. I know it sounds like a REALLY stupid question, but it's a BIG problem for me right now. My damn dome light won't shut off, actually I don't think anything is wrong with the dome light itself. When i put the key in the ignition and start the car or turn the key back to acc. it stays in the annoying DING DING DING mode! Even when both doors are shut, just to clariyfy I never got an owners manual with the car so I don't know which fuse to look for to yank out. Can anyone help? I wondered why yesterday when I went to start it to go to a doctor's appointment the battery started the car with just barely any power. It started first turn of the key and didn't roll over a bunch like a chevy does , but it was like "RR, Vroommm" as opposed to the usual "VROOMMMMMMMMMMM I'm BADASS!" Any suggestions fellow GT'ers?