tortoise breathing

Question
I very recently got a bell's hingeback tortoise but I already am a bit worried about it.
It lives in a vivarium and I keep the temperature at between 25 to 27 degrees Celsius depending on the time of day by using a heat mat and a light bulb (ordinary rather than special UVb one, should I change this?) all my tortoise (female) has eaten is banana since she got here but I dont think that will be my problem as I will continue to experiment with other foods until I find something to balance her diet that she likes.
my main concern is that her breathing is audiable, I have read on care sheets that this is not mean't to be so and it should be silent, I am worried that this could be highlighting illness in her but I was just wondering if my concerns are at all valid. It isnt particularly loud breathing but is substantial enough that I can hear it. is it due to her vivarium being too small, or the temperature being wrong. I have tried keeping openings for air flow but I havent noted any difference in her breathing. However I havent seen any other signs of discomfort or health issues. I am sorry if this was a waste of time but I thought I may as well just check. thankyou for your time.

Answer
Yes, you should be concerned. Yes, you should be using UVB lighting. If I have to say that, then frankly you haven't done enough research on these animals, and I advise you to look into it and correct your husbandry before the matter worsens. I would advise a veterinary visit. Respiratory illness is a common killer of chelonians. If you wish more detailed information then I'm going to have to ask that you follow the directions and answer all questions in my instructions.