Burning in upper back, shoulders, and neck.

I read many other topics in this area, but none seem to match my symptoms. My problem only occurs when I lie down to sleep, sometimes before I fall asleep, sometimes after I've been asleep for a while. It's a little hard to explain the feeling, but it's close to a burning sensation. It occurs in my upper back, shoulders, neck, and slightly up the back of my head. It doesn't happen every night, and in fact had only occurred about 5 times since the first time about 3 years ago. But for some reason it has now occurred 3 nights in a row. It feels worse when I sit up or make any movement, and only lasts about 10-15 minutes. When it's over, I feel relieved...compared to as if I were holding my breath and finally took a breath. I am a smoker and had been attributing it to that fact. I have also had a mild stroke and have Sickle Cell Disease (yes I know these don't match with smoking, I know, I know, I'm trying to quit). My doctor has only speculated as of yet, no tests have been run. Any info you can give me would be helpful.