Bearded Dragon coughing

So, my bearded dragon is roughly 10 inches long and I bought him in May. He is a juvenile. He is in a 40 gallon breeder as of now, his substrate is reptile carpet, his basking spot never falls below 100 degrees Fahrenheit and i use a 150 watt basking bulb (uva for day and infrared for the night time). He has a 10.0 UVB bulb but it doesnt span the entire top of the cage, its not a coil but it's not like the long tube idk how to explain i can upload a pic if nessecary. I do want to upgrade to a UVB that spans over the entire length of the cage but the cheapest one i can find where im at is about 200 to 250 dollars and i simply dont have that kind of money. I feed him crickets daily, as many as he'll eat daily sometimes i do worms too and plan on providing more greens than i usually do right now because i know i fall short on that aspect atm. He does have a large water dish but with it his humidity is usually only around 40-50% for the whole viv. He has been to the vet and the vet confirmed everything was good and i was doing everything right with him, but he had a small case of conjunctivitis in the eyes about a month and a half ago that has since cleared really nicely. I just switched him from his 20 long like 2 and a half weeks ago and hes still adjusting and has been a little stressed. His bowel movements are regular. Everything seems fine except he is rubbing his face on his decor and he coughed a couple of times today. Im worried about a respiratory infection. His eyes, ears, nose, mouth, and everything look good. Im prepared to take him to the vet within a week if nessecary, but should i even be worried? I have overreacted with his health on multiple occasions lol. And sorry for all of the information! I wanted to cover any question that might be asked. His uva heat bulb and uvb are on for 12 to 14 hours a day and he gets 10 to 12 hours of nighttime. I plan on getting a timer for the lights so that he can have a more regular schedule but as of now it is a little irregular haha. I clean his tank about every week or two, as well, and i just cleaned it yestersay.

So, his coughing sounded like a squeaky toy and the rubbing his face on his decor was something he did with his eye infection, but this time its his chin and mouth area he is rubbing instead of his eyes. Any thought on what may cause it or if it is even something to worry about? I dont want to rush him to the vet unnessecarily because last time he went to the vet it was really stressful for him.

My guess is that he has a shed coming on and he is just expanding and contracting his body to help shed the skin. The face rubbing is also consistent with a shed. Unless you see excessive mucous around his nose and mouth I wouldn't worry too much about a respiratory infection for now.

As far as the UVB light goes, is it a T8? What is the wattage and brand? There are some excellent UVB lights available for much less than $200 but it kind of depends on which country you live in.

Okay awesome!!! I figured I was overreacting hahaha. As for the UVB bulb... i found the box for the one I am using and it is a zoomed reptisun 10.0 desert bulb, 120v, 26w, with a E-26 base. And the bulbs around where I live aren't bad price wise but a decent hood for the bulb is where it gets pricey.

OK the 26w version of that bulb is so so. A 22'' T5 would still be a good upgrade but for now I'd keep that in a reflective fixture and set it about 6-8'' above the basking area for best results.

Sorry for the very late response!! Ive had technical difficulties lol. Thank you for the info. Hes stopped coughing and i gave him a bath to help with his shed so hes stopped rubbing his face as much. I also adjusted the placement of his uvb so that its closer to him and am planning on an upgrade. Hes doing good! He did have a fall when i had him out yesterday though so im very worried about that. He was maybe 3 and a half to 4 feet up. He landed on hardwood floor and then ran around my dining room like a lunatic. There are no visible signs of injury, he may be a bit bloated but its difficult to see especially since hes kind of mad at me and doesnt want to be held anymore. He also hasn't used the bathroom since yesterday. His activity is pretty normal and hes eating well. I am waiting for his bowel movements right now before scheduling a vet visit because he seems fine.

Update on my dragons fall: he did just have a very, very large bowel movement. It looked relatively normal. I squished it with a white tissue (gross) to see if there was any blood. Theres nothing abnormal. It looked like he hadnt chewed his greens and bugs very well idk if thats normal but it definitely wouldnt be related to his fall imo. He still seems a tad bloated though. He also is a bit dehydrated (based on his droppings) which is a pretty common issue with him (he isnt very interested in drinking water and sometimes refuses his greens). I may still take him to the vet even though he seems fine. Im going to give it a couple more days of obervation before i schedule an appointment though.