They won't do well inside; not for very long.

Even saplings should be given a cold season outside...protected from very cold temperatures so that the roots don't freeze solid. One reason that they are growing so awkwardly is because of the indoor environment.

These plants perform best in full sunlight, and there is no way that you can approximate that inside, without an artificial lighting system.

AND...woody plants just plain don't like normal potting medium, either. If you are going to keep them in the containers rather than plant them outside, you might want to find a regular bark-based nursery mix.

Nope, don't pinch the growing point out. They will just have to grow a new one in the same place, and may end up looking kind of crooked.