Need more specifics. Is the outdoor unit running (fan and compressor) when it was blowing warm inside?

one of the two or both isn't running if it's just circulating room temp air inside. If the out door fan is running, grab the insulated lines copper and see if it's cold, that's the quickest was to see if the compressor is running if u can't hear it. I've had a lot of compressors overheating and shutting off on overload lately due to stopped up coils outside.