your either loosing your mind...

or your leaking a fairly good amount of refridgerant into your car cabin. heres a simple test. if your car is in good condiiton and doesnt overheat do this:

turn car on, let it get to normal operating temp
roll up all windows, and close sun roof
turn on A/C full blast and temp on cold
come back in 15 minutes and open the car
check the inside temp

if its still cold run the test again after letting your car vent out

if your leaking coolant your car should stop cooling when its low, the compressor will turn off when it senses low coolant.

thats a good test for a leak.