Chest tightness & shortness of breath with normal x-ray & CT scan

Patient: I started having chest tightness and shortness of breath about four months ago, which started off as being intermittent and gradually got to the stage where it was constant. Around the same time, there was about a 1/2 week smog episode in London (where I live).I happened to have a check-up scheduled at my local medical centre, during which the asthma nurse said my peak flow was a bit low (I’m 31 yrs old and hit 550), so she told me to take a blue salbutamol inhaler. I did this only sporadically to begin with, but then found I was using it 4/5 times a day, sometimes without any relief.I went back to the doctor who recommended that I see a cardiologist. He gave me an MRI scan of the heart, which came back normal, after which I was referred to a respiratory specialist. He put me on symbicort for a couple of weeks, which elevated my peak flow readings to 620/630, but I was still getting shortness of breath and chest tightness, including in the middle of the night. He ordered blood tests (which came back with a dust mite allergy and a slight deficiency in iron – although this was within normal limits) and also ordered a chest x-ray and lung ct-scan (with contrast, in case there was a blood clot). Both came back normal.He believes that the problem is anxiety related and referred me to a psychiatrist, who I am due to meet next week, and he has mentioned the possibility of some CBT.Also a couple of weeks ago I developed constant daily headaches that did not seem to clear with over the counter painkillers. Again went to the doctor, who referred me to a neurologist, who gave me a brain MRI. Again, came back normal, except for some sign of congestion in my sinuses (likely because of a cold I developed about a month ago). That cold has still left me with a sense of taste and smell that is not completely back to normal.I don’t know whether it is related but I also have a “clicky” jaw, which the doctor has told me is temporomandibular joint disorder. It doesn’t hurt, but my jaw does click constantly when I eat.Although the chest tightness and shortness of breath have settled since the CT scan result, they have not completely disappeared. I have been sleeping better, although yesterday I had quite bad shortness of breath in the evening and woke up two or three times at night short of breath.I’m really not convinced that anxiety is the problem here, do you think I should go back to the respiratory specialist? Are there any more tests that he can perform?

Symptoms: Chest tightness, shortness of breath