Thanks for responding - your answers calms me down a bit. If i had done this prior to my concussion i would not have been worried at all, but due to the close proximity i was worried that the shake of the brain might have been enough to sustain permanent damage due to a destruction of already bruised neurons.

Do you guys know how many G's such an impact might create?

At the start of the motion my head was 1 m above the matress, it took me 0,5 s to reach the matress - and the matress gave 5-7 cm before my head bounced back. It was a circular motion as my head kind of traversed a quarter of a circle from the initial erect position to the horizontal matress.

Anyways ill stop worrying and get on with my life. Thank you.