Hesitation between 1800 to 2200 RPM's

I have a great Volvo 2001 113,000 miles in great condition, have had all services completed when recommended, most recently (last week) new spark plugs, timing belt 3mths ago. Around 2000RPM’s I’m getting a ton of hesitation, lunging, choking (no sound) even if my foot is not on the accelerator. In addition, the air conditioning is not working…not blowing cold air. Anybody…please help:)