There is no limit to the amount of dead wood you can remove. So IF these branches were all dead, then you didn't harm anything. However, the fact that they died would suggest a serious health problem with the tree that had badly damaged it, since it's not normal for branches on the upper portion of the tree to just die this way.

Additionally, some of the trimmed branches look like they may have still been alive. If that's true, then you may have harmed the tree by removing them.

In the future it's best not to remove more than 25% of the living canopy at one time. If you're unsure what's alive or dead, you can find out by making a small scratch in the bark to see if there's still green beneath. Green and moist means the branch is alive, even if the surface is brown or has no leaves.