My AC is blowing hot - Refridgerant Pressure not consistant

[gchan]

My 03 V6 Accord's AC starting blowing hot on the driver's side the other day and just yesterday now the passenger side is blowing hot too. I checked to pressure so that I can add a can of 134a refrigerant and the pressure kept starting at around 30psi and then dipping to 10or15psi and then raising back up and then dropping again. I was told that this could just mean i was low on the refrigerant and that I should add some. So I did and while I was adding it the pressure would now switch back and forth to around 40psi and then drop to around 30psi and back up and down like before.

After about ten mins of adding refrigerant the pressure all of a sudden just dropped to 20psi and stayed there. what does this mean? did i break my car??

Please HELP me. I just had a baby and my car was the only car where the AC actually worked and its getting hot here in Houston. Im very desperate please HELP!!!