Q: Did I harm my truck by incorrectly putting it into 4x4 high?

Hello,

I was driving up an icy hill. I was in 2 wheel drive and couldn't make it up. I backed a bit down the hill to a side road that was a little more level, but still on a bit of a slope. I put the truck into neutral and with my foot on the brake switched the electronic shifter to 4x4 high. The indicator came on in my dash panel. I put the truck into drive and was able to get up the hill. After parking I looked at the manual and it said that to shift into 4x4 high, one should be moving forward (up to 55mph) and then just use the electronic shifter to switch into 4x4 high. That is unless the wheels are slipping, which they probably would have been in my case. It said to put the truck in neutral with the foot on the brake only when switching into 4x4 low. Just wondering if I did any damage by putting the truck into 4x4 high with it in neutral and my foot on the brake.

My car has 90000 miles.
My car has an automatic transmission.