Mary Margaret
I don't think you will. I mean, you could see if any of the magic users would be able to tell, but honestly? I think you just need to trust in yourself. Despite what happened in the Dreams, despite whatever changes may come from it should it happen regardless of your actions here, you know who you are. That won't change it.
Just because I turned into a werewolf doesn't mean your heart will turn black, though. The wolf thing is genetic. The state of our heart? That's on the choices we make and what we do with our lives. Regardless though, you're still my best friend, no matter what happens.