Weird energies

Yesterday's practice was heavy. The revenge of that of Tuesday? I admit I was too eager to say that there is no soreness...

There was also some weird negative energy in the air. Where does that come from? From my own head or from the (negative) girl next to me? She is a friend and always a very friendly person, but I always get a kind of negative feeling with her. As if there was some hidden agenda or lack of self-esteem by herself. You know how with some people you are really at ease and they give you a lot without even knowing it themselves - I believe they give because they are so well within their skin. Well, when someone is not well, that takes instead of giving. And often people themselves don't know how they are not well. So sad. And that sadness takes off energy from the ashtanga practice. Can it?