IS THIS NORMAL?

92 190E 2.6, Driving along at 70 mph, I raised the windows and
switched on the A/C. It was as if the car went into a lower gear when
the compressor engaged and I could actually feel the load on the
engine so I switched it back off. No squealing belts or unusual
noises. System was just recharged. A/C was unused since last
summer, last checked in April was blowing cool... also noticed,......
After last weeks recharge, air from vents was a damp cold, now feels
drier, not as cold There is a freon leak somewhere, but what else
should I be looking for?

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