I have a 91 Ford Explorer that I was useing to apply pressure to a tree limb so I could trim a tree.?

It seemed to not go into park easily when I had applyed pressure on the tree limb. Now when I go to put it in overdrive it makes a whine noise and wont go in overdrive at all but if I let it idol down it WILL go into drive and drive just fine. I had replaced the modulator a short time before this happen. Any ideas what it could be? I have also pulled the pan and tail shaft section and didn't see any parts broken or anything.