I experience high anxiety most days and it feels like my brain is so busy with catastrophic thoughts rushing around, light headedness, weak legs, racing heart etc

This evening I had a really painful headache come out of nowhere and my first thought was that something ruptured in my brain and I was going to die. I was home alone and started to go into panic, but I was desperate to stop it. I told myself to lie down, and support myself until it passed. I talked to my "anxiety voice" and reminded it that I've felt this way before and nothing bad happened.

After a few minutes I feel as though I went into "freeze mode". Instead of my brain being busy and loud like it is always, especially when afraid and anxious,  it was completely silent. I sat staring into space for half an hour. I felt like I couldn't get up or move or something terrible would happen. When I did push myself to get up I felt like everything was moving in slow motion,  like I was dreaming and I couldn't keep thoughts in my mind. I felt afraid but only on the surface. Deep down I felt nothing and like my brain was concretely still. No racing heart, breathing slow and steady. Its been two hours and I still feel like this and it's beginning to really scare me.

This is something I've never experienced before after 10 years of bad anxiety. I'm so worried the headache was related and that something is wrong. I'm afraid to sleep as I think I will end up with a nocturnal panic attack or worse.

Have you ever felt this way ?