I would say you are having a problem with the turn signal as on those cars you push back on it to turn on the bright lights. May need replacing.
Rowefast is correct. The multifunction switch (turn signals and high beams) likely needs to be replaced.
Mine is doing the same..... Found this, hope it helps. I will be changing mine this weekend. http://www.instructables.com/id/How-to-change-a-turn-signal- switch-on-04-Pontiac-/
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