Often if you de-select an object, zoom in closer to the object, then click on the object, different temporary dimensions will appear. This is because you are excluding from the view those objects to which the prior temporary dimensions were connected. Temporary dimensions only attach to objects within the modeling window's visibility, so you could try zooming in and using your middle mouse wheel to adjust what the screen shows, then selecting the object once more.
Having said that, usually temporary dimensions run perpendicular to a wall rather than parallel to it. However, in this case it would be simple to manually place a linear dimension there and adjust the wall using this new dimension line.
