Waw! Loads of interesting points there everyone, thanks.
I had relaxation excercises such as raising and lower shoulders by alternately tensing and relaxing in order to notice the relaxation better as well as just stretching the neck muscles with different head movements. Mainly just being more aware of how you hold yourself and being aware of tensing upper body.
Frankey - Really interesting what you mentioned about relaxing your tounge and throat as I get a lot of pain around this area as well as pain inside my throat when my voice begins to break. Silly question...but how exactly did you know whether you were relaxing your tongue enough?
Couchtater - I've discovered I have problems with acid reflux and like you I think it'd been going on for a while before I realised. I seemed to feel like I had a permanent cold for ages and my voice came and went frequently over a few years before I discovered I had problems with acid reflux. I've restarted taking tablets for severe acid reflux symptoms but I guess I just got a bit impatient as I'm back in class tomorrow and need a short term fix also.
Huge thanks to everyone for their contributions, now have a few tricks up my sleeve to try and preserve my voice over the next 3 teaching days. Doctor is aware of this issue and has offered to sign me off if I need time for my voice to recover so I guess I always have that option if things get worse in the next few days.
Fingers crossed for a few quiet days in class... may have to whisper the lesson if all else fails...allways confuses the children a little!