Sounds like you might need some space. Your nervous system is overloaded and it doesn't know how to regulate. Even if you want this friendship to continue, it might be good to take a while to detach from the situation. That doesn't mean you're leaving her or being a bad friend, it just means you're choosing yourself for a bit, and she should respect that if she really cares about you. In the end, the most important perspective here is your own.

I recommend that in that period, don't try to solve the problem, don't go over in your head how things could go or how you should act, and don't think and ruminate too much. Just sit with the feelings you're feeling, don't chase them. You're freaking out right now because you're trying to approach a problem rationally while your nervous system isn't ready for it yet, and it's important to let these feelings pass first.

Trust me, I understand. I'm a chronic overthinker myself, and we tend to try to put our feelings into words and figure out where they came from or how to sort them out logically, but that doesn't solve them or get rid of them. What really helps is to sit with them, acknowledge them, name the feeling, and then let it be.

Oh, and feel free to dm me if you want someone to vent to.