See this article The excerpt appears on page 4.
It would appear that the halachah of rodef combines the concept of
saving the victim's life and punishing the aggressor into a single
law. For ordinary sins—even those that carry the death penalty—a
person cannot be punished before the sin is actually committed. With
regard to a potential killer, however, whose murderous sin is liable
to cause irreparable damage, the Torah obligates the killing (if
necessary) of the rodef, punishing the evil deed in advance of its
This combination emerges from the writings of the Rambam
in Moreh Nevuchim (Part 3, Chap. 60): This law… is only permitted in
two cases, which are the case of somebody pursuing his fellow to kill
him, and the case of somebody pursuing a married woman, for this is a
wrong that cannot be repaired after it is done.
The article also states,(it's a long article!) that, ideally, if you can prevent the person from pursuing you further, without killing him, you should do this first. So, offhand, it appears that what you and @user6591 did posed no problem whatsoever. Note, the parentheses in the 1st paragraph "(if necessary)". I infer that if you are allowed to kill, you are certainly allowed to injure / disable the rodef.