First of all, the 5.0 Reptisun T5 will not help your beardie one bit, and since she's never had a
UVB light I'm assuming she has MBD already, and my be stunted, have digestion and nutrient absorption issues, and she will not get better and start to thrive without very strong
UVB light for at least 14 hours every single day. The 5.0 T5 is for tropical reptiles only, not desert reptiles, and does not provide nearly enough
UVB light for a healthy beardie, let alone a sick beardie that has never had a
UVB light. You must get her a 10.0 T5 High-Output UVB tube, either 18" or 24" (NOT THE COMPACT VERSION, IT'S NOT GOING TO HELP EITHER!) So if you already ordered the 5.0 T5 tube and a matching T5 rated 18" or 24" tube fixture, as soon as it arrives I'd call the place you ordered it from and tell them you want to exchange it for the 10.0 T5 High-Output in the same length, pay the difference between the two, which shouldn't be much at all, and get it back in the mail so the 10.0 will arrive quickly. If you ordered the 5.0 T5 Compact bulb then it's really completely worthless and you must return both the bulb and clamp lamp or dome lamp, and order either the 18" or the 24" Reptisun 10.0 T5 High-Output UVB tube and a matching length flourescent tube fixture immediately. PLEASE DO NOT IGNORE US AND SIMPLY USE THE 5.0 OR ANY COMPACT VERSION, SHE NEEDS AND DESERVES TO FINALLY HAVE PROPER
UVB LIGHT!!! And please mount the 10.0 T5 High-Output UVB tube within 11" of her main basking spot, right alongside the bright white basking bulb!!!
It sounds like an upper respiratory infection, but the only way to know is to take her to an experienced reptile vet and have CULTURES DONE! Do not just take antibiotics after a vet simply looks at her, that seems to be the trend lately. Upper respiratory infections can be caused by a bacteria, a fungus, or more often than not both, so she may need both an antibiotic and an antifungal med, so they ABSOLUTELY MUST DO A CULTURE AND SENSITIVITY!!! Aspergillus is a very dangerous fungal infection that is often the cause of respiratory infections in reptiles and birds, and if misdiagnosed and given the wrong medication it can end badly.