LOL…I definitely would’ve been the one who laughed and stayed behind.
That being said…yes, I do believe the other woman over-reacted. UNLESS you guys said something specifically about her…if it was general jokes that made her uncomfortable…as an educated adult (I’m making an assumptio that she’s an educated adult…), she could’ve excused herself and left. Especially when you’re around co-workers…losing your temper and throwing a temper tantrum doesn’t do you (or your career!) any favors.