Having wheezing and breathlessness during winter season. Suffer cough and congestion and yellow phlegm. Suggest treatment?

I am British and registered with the NHS. I have ongoing respiratory problems, mainly when weather is wet or cold it seems - during the winter. This is wheezing most of the time, breathlessness sometimes so severe I cannot sleep and cannot walk easily or climb any steps; cough from the chest, congestion and yellow phlegm. If someone sniffs on public transport I immediately get a fever and severe breathlessness. I am not happy with the service from my GP - this illness started three years ago when I had pneumonia, it took the nurse two weeks to realise something was wrong and I was immediately sent to hospital and given oxygen for most of my stay. Afterwards I continued to complain of my symptoms and was given no advice. Eventually one doctor prescribed antibiotics which helped a lot and an inhaler which nobody explained to me how to use. On another occasion, after my breathlessness had forced me to sit outside in the garden half the night, a doctor told me it was probably a panic attack. They give me the breathing into a tube test and accuse me of not trying. They send me for chest xrays but they never show anything. The last time I visited in May (before the summer) after I had been off sick and unable to sleep because of breathing difficulties for three nights the nurse said I was not an emergency. At my insistence she prescribed antibiotics and a new inhaler which I have now found out how to use. In the summer I had a private consultation with a private health company which reported to me that I am at stage 2 of GOLD COPD standard. Once again I am ill, worried about having to have time off work and really not knowing what to do when the breathlessness starts. Changing my GP isn't really an option I think and making a complaint won't help but is there somewhere I can get proper advice and treatment for a condition that isn't improving and seems to get worse please.