shaking head, ear drums, heart slows down

I have a similar or same problem.When I put myself to sleep and before falling into deep sleep,
1- my head starts moving in a jerkily manner to the right or left.
2- I can feel it but can not stop it or even open my eyes.
3- I am aware of what is happening and I can hear my wife telling me that I am shaking my head and I can talk to her back that I know and feel it but can not stop it or open my eyes.
4- when the head shaking starts I feel ear pressure/drumming,
5- I feel like my heart slows down.

I am 32, and I never drank in my life. But I do smoke.

Any help or ideas what the cause might be ?