A/C Condenser- HELP
 

I was told I needed a new AC condenser in my 2001 1500, I replaced that myself and upon attempting to recharge the AC, my compressor is kicking on and off repeatedly. It says the truck will take 2 lb of refrigerant I think I didn't even put in 8 oz and it's reading in the red when the compressor kicks off. How do i fix this? I need AC, it is getting to hot in the truck for my 2 year old.