I would get a magnifyer to look threw at the fabric and needle. I have the same problem as you and I am not yet 30. (only a few months till I get there) I hunch over all the time and it is a real pain. Also the chair and table height are a problem. If you can lay down on your back or see a back cracker person I would suggest that maybe once a month depending on the amount you are sewing. a couple of months ago I was hurting and in so much pain that I was on the floor and couldn't get up and was having trouble breathing. I went and had my back adjusted and it has been better since. I try to not tense up when I am sewing. I also hunch so close that my head rests on the top of my sewing machine sometimes. that is when i am really tired and having trouble seeing and my back and shoulders are sore.