Good luck... you might just ask her, instead of apologizing (or asking if you need to apologize)? Like, "Hey T - I felt like I may have seemed a bit weird last week because of my med change. Did you notice that?"

Good luck... I know sometimes I feel like I'm coming across oddly (sometimes I feel like I'm talking really fast, and afraid that I look more manic or overly excited). Sometimes I remember to check it out with whoever I'm talking with, and usually, they haven't noticed anything at all... so it's just how I'm feeling, apparently.