How well do you pick up on positive or negative energy ??

I do believe there's a sense of positive, or open energy, and negative, closed off energy when I first see or meet someone. There's someone in my extended family, she introduced me to her then bf , now hub. The second he turned to me, it felt negative or closed off. Monotone voice, stared at me bluntly saying hi. And I just could feel a closed aura.