Dear baihui1234:
February you had “a nervous burnout” that included “adrenaline rushes” that brought about troubles sleeping and fatigue. You recovered but at times when you remember the nervous burnout, you “get weird body sensations… almost like a mild unconscious faster breathing”, and when you are active, it is a “tension in head, neck, chest, belly or spine” and sometimes you get startled when drifting into sleep.
I think it is something like this: the big nervous burnout you experienced was like an earthquake, and what you have been experiencing since is a series of aftershocks, mini earthquakes that follow the big earthquake.
If you continue to live your life mindfully, aiming at calm, the aftershocks will lessen and lessen, I am thinking.
anita