BINGO! Just got the results of diagnostics yesterday from the auto repair shop. My A/C is leaking through a bad evaporator. He said that was also likely the cause of the black mesh foam/filter stuff I had coming through my vents. The freon leaks into it, makes it oily, and then it disintegrates. His estimate is $1k - 1100, which I will definitely NOT be doing. So, looks like it's time to hunt for a new car for me.
So, Magda7290, it may very well be a bug filter in your case, but I'd lean towards the evaporator. And if you're having trouble with getting cold air from your A/C, you can consider it confirmed.