Possible overfilled Freon?

I just added Freon I put it to go between the 20 and 40 mark in the green spot of the gauge. That day it worked fine but the next day I was getting ready to leave and it was hot so I turned on the A/C and it throws out cold air but then it started smoking from my engine. I turned the car off and it stopped smoking I looked under the hood can't tell where the smoke was coming from. I looked underneath the car and it was leaking but I don't know from where and it's a clear liquid. And so now when I turn on the A/C it smokes from my engine and I have some leaking that shows in the driveway but I don't know where it's coming from. Did I overfill the Freon? Or is it something else?