It might be best to seek professional medical assistance soon since you suspect this is connected to breathing problems during sleep and potential suffocation.
Shaking during sleep could be due to a whole lot of reasons from psychosomatic responses to medical disorders, psychological or psychiatric issues.
What's pertinent is your medical background, habits and patterns and an accurate as possible description of the symptoms, i.e., the movement, range, timing, duration, how violent the movements are and so on. Better yet, record a video over several nights, through out the entire night if possible, till you capture an episode.
You might want to consider discussing your symptoms with your doctor, and what tests and trials are available. I don't know if the hospitals here have a specialized sleep center with experience in diagnosing people with rhythmic body movements or seizures that might be associated with breathing disorders.
Meanwhile, read up on sleep disorders and specifically, 'shaking during sleep' and 'violent shaking during sleep due to breathing problems'.
http://hubpages.com/hub/Sleep-disturbances-with-body-jerking
I hope you find out what you need to and that everything works out well.