Every experience changes who we are. But if you mean falling to the Dark Side, I'm not showing any of the typical signs or attitude changes, as far as I can tell, nor am I as likely as Kreia was to up and murder people for a philosophical point.

Still, it's not like one can really trust a self-assessment of their own mental state. If I had fallen to the Dark Side, I wouldn't likely be able to even tell until I looked back on my actions objectively.