cc, body language couldn't be further from my PhD! And what you said is precisely what I thought - her concern is my work and nothing else.
I am hoping it was a one off, though I am upset that she brought up the fact that I have an ill family member. By doing so I believe she crossed the line and made her remarks too personal. Not only that, but having my arms folded has absolutely nothing to do with any of my family issues! Why bring it up?
Though, I have learnt something...NEVER sit with your arms folded (regardless of the circumstances and whether or not you're freezing)!