How easily I can lose my cool

Saturday morning at around 1, I got a phone call to my cell phone from a number I didn't recognize. I freaked out. I suddenly got very cold and my whole body started shaking--my normal response to that kind of fear and anxiety. Why when I don't really expect her to call me at such an unreasonable hour?

Even though I don't expect her to show up unannounced, I look out at the parking lot every time a car pulls in.

I am not afraid of her in anyway. I am actually looking forward to seeing her.

I am afraid that my life, which I am finally getting in order, will be totally derailed when she comes home. I still feel like I have a fragile hold on things right now. I might be wrong about that, but until I have tested it, I can't be sure how I will respond.