Tucker13,

Welcome to NeuroTalk.

I have an idea what may be happening but need some additional information first.

How long has this problem been going on ?

When the manhole cover was dropped, did it startle you ?

Do the other vibrations or bumps startle you ?

Have you checked your blood pressure when you get these symptoms ?

How many other concussions or head hits have you suffered in your life ?
Do you spar or do hand to hand combat training ?

Did you play sports in school ? What position? Any head hits or concussions ?

Have you endured any traumatic episodes in your job or otherwise in the past few years ? Has your concern for your personal safety on the job changed in the past few years ?

Have there been any other struggles, challenges, or big changes in your life in the past few years ?