Car will not start

I went out o start the car for school and it started right up no problems or anything. Once I was driving I tried to plug in my invertor so I could plug my wall cell charger in and all my invertor would do was beep saying there was a fault. Got back home turned car off. Went back outside about an hour later to leave and all it would do it a fast clicking noise. Moved cable around jumped it off and was good until yesterday. Did not have any trouble with it all day until yesterday afternoon went out to leave and again clicking noise. Jumped it off today and left it running for about and hour and half including driving it and idling. Turned it off tried to restart it and just clicking again. Plese help! Only vehicle and have to get my son back and forth to school.