warmer air AFTER recharging AC

Just adding freon is not always the fix for a system that doesn't cool.

THESE WORDS should be permanently engraved in every store above the refrigerant shelves!!!!

Other problems:

Could have "slugged" the compressor with liquid and ruined it, ruptured a valve or broke a rod. You will not always hear this

Could have somehow introduced some moisture with your charging getup. A drop of water will freeze when it goes through the system metering device, instantly plugging it