The last two nights, right bedpfore going to sleep i've felty trembling in my body starting in chest. what could cause this?

Unlikely organic: Because your symptoms are not present until just before bedtime it seems unlikely that they should be caused by something organic within the body. Having said that, if you have not had a good physical and laboratory checkup in some time I would recommend you see your doctor. They may wish to run a few tests such thyroids, cholesterol, and a basic chemistry panel just to be sure of things.