Need Help Car Won't Start

[Rem152]

I just got home and parked my 06 mustang get as I pulled the auxiliary cable from my phone the radio started to flicker on and off but the car was running fine.... so I shut the car off and when I went to go start it the thing wouldn't turn over at all it would click click click but wouldn't start at all I hooked up my act and all I got was p1000 and I cleared it but to no avail the car would not start it wants to turn over but wont... the interior lights worm fine but my headlights will flicker and shut off so guys please please I need help with this because it's really my main means of transportation right now... any advice would be greatly appreciated

 

[jpplaw]

Problem with Battery and/or alternator