I'm not sure which but I've got a constant ache in my left shoulder and can't move my neck backwards very far at all (having to drink with a straw....or leave 1/3 of my drinks) as it's too painful to tip my head back. When it's painful it's like a sharp stabbing pain - don't know whether I've strained it (first noticed it yesterday after I'd spent the entire night in almost the same position) or trapped a nerve.....
Either way is there anything I can do to alleviate the pain - was going to try some deep heat on it earlier - until I read on the box "consult your doctor before taking if .....breastfeeding....".......