I've had these. They're awful.

For me, it's usually a sign that I'm mentally exhausted. Of course, waking up in the middle of the night with panic, and not being able to get back to sleep, feeds the cycle.

What has helped me in the past is recognizing it as a sign of exhaustion, and then focusing on resting more- including during the day if possible.

With the night panic, sometimes it helps me to just sit upright in bed for five or ten minutes. No idea why this is, but the panic will go on if I remain lying down. Once the initial wave passes, I lie down again and just focus on how comfortable the bed is. I don't worry about falling asleep again (or I won't be able to), but rather focus on letting my body feel good in the bed, and letting it go slack and get rested even without sleep.

I hope you find some peace soon.