Rick - breathing won't have hurt your back, but your back will hurt when breathing....as one who has in the past had a lot of back trouble, I sympathise. If it's a recent thing then its posture - what do you play? I invested in an osteopathic cushion some years ago, which makes me sit at an angle of about 17 degrees, I think it is. This pushes your pelvis forward and aligns your spine, and its helped me. Go to a back shop and get one, but in the short term go to an osteopath and get treatment. Don't get worried if your back "cracks" when you move - all this means is that its supple, most problems come if your back never cracks, which can mean that your vertibrae are jamming together and this can lead to trapped nerves and pain that will make you weep! Is your bed too firm or not firm enough?|
Lots of tuba/horn players get back trouble, from the weight of the tuba or the twisting that holding the horn involves. If you've not had pain beofre I wouldn't be too worried, but if it persists check it with your GP and go to an osteopath. Osteopaths have helped me a lot more than GPs.