You can have a GM fix this in-game. Arrange some time with one to have your head fixed.
Before you do this, however, you need to figure out which head is the correct one. Do this either by starting (but not creating) a new character of the same gender and race and counting the heads forward from 1 until you find the right one. It can also be done by using the toolset by associating a module with the Layo HAKs and building a creature (of course with the same gender/race) and recording the numeric ID of the correct head.