i cant sleep at night because of a weird extremely uncomfortable sensation that happens when i fall asleep.  it seems to start in the middle of my upper back and spread out to my shoulders and if i dont move a muscle the feeling gets so intense and overwhelming and causes me to twitch or move around.  i sometimes get up and do push ups or what ever it takes to try and make my body tired to get rid of this feeling and fall back to sleep.  it started happening i guess and little less than a year ago and is getting worse, it has been happening now almost every night.  its a feeling that i can just feel lingering and before i fall asleep i just know that its going to intensify and i will wake up and not be able to sleep well.  i just need to know whats going on?  is this my nervous system acting up, what is causing such an uncomfortable feeling in my body and not allowing me to get proper rest?