AC Too Weak
 

Hi, I have a 2001 Camry CE 4cyl. The main problem is that the AC is too weak. I went to the store and got the refilling thing with the gauge and checked the pressure as the instructions told me so. It was all in the norm (although I added some more, still in norm). The AC is still too weak. Infact now the driver side blows colder than the passanger. This gets a little hard when its over 100 outside. A few days ago I turned the AC on full and opened the vent, it got a bit colder, but in a few minutes the engine began to overheat. Quickly turned it off. I have no idea what to do. Advice would be greatly appreciated.