Help please: Adding refrigerant to my 06 H3...which port is the Lowside?

[jersey]

OK...I checked all my resistor work, no apparent problems. I checked every fuse in the box, no problems. I started up the car and watched when surprisingly the compressor clutch turned on. That's thee good news, but it is cycling rather quickly. And its blowing cold air, but no where near as cold as it was originally. I added another can of r134a, still the system is working, but not as cold as it should be. The second can hasn't improved it over where it was originally. So maybe there was a loose connection somewhere? But I guess at this point, since I don't have either the knowledge or the gauges to safely proceed further, I'll bring it to a mechanic and have it checked.