Am I the A-hole?

So, the other day I went to my friends house (let's say her name is Barbra) for a overnight. She has a history of being somewhat abusive (kinda ig) where she would hit me (not playfully) or push me, ect. But other than that and her constant need of m6 attention, she's a fairly good friend. So me and her were just watching some true murder stories when we started messing around a bit. We kinda high Fives each other until it hurt to much and we had to stop. Then, she flicked my forehead, and I kinda playfully acted like I was gonna bite her hand. Then she pulled away and got mad and she in a deadpan voice word for word "If you bite me, I'll kill you". That scared me ngl but I didn't say anything, I just made sure to leave her house as soon as possible and now she's all mad and upset at me. Was I overreacting? Should I just have brushed it off? Should I confront her? I don't know what to do, so I'm asking you guys and I'm really sorry for wasting your time.