I have had shivers or tremors over the last 15-20 years. They started when I got out of the shower. They were quite violent. About 5 years went by and the shivers returned. This was another violent episode after a shower that lasted about 30 seconds. I went to several doctors who made extensive test and found nothing. The tremors then occurred only at night while I was falling asleep or during sleep. They increased in frequency but less severity over the last 15 years. I have seen many doctors during that time. They say it is all in my mind. Now they occur almost every night. Has anyone experienced these symptoms.