Breathlessness can be anxiety provoking when trying to get a job done and exert yourself. There is a lot of research that suggests that movement of air across the face and nose can reduce a persons sense of breathlessness and hence their level of anxiety . https://www.ncbi.nlm.nih.gov/pubmed/20471544
The main benefit is that it reduces your recovery time and is a self management tool you can take anywhere you need it. If you don’t have a hand held fan in the moment then sit by an open window or on the verandah so the breeze crosses your face, especially the nose and mouth, and it may also help.
A hand held fan held 15- 20cm from the face works through cooling the nose and mouth with receptor messages sent to the brain altering the person’s sense of breathlessness, if your nose is blocked or mouth dry then it will be less effective.
The Lung Foundation has fans for sale in its online shop, alternatively they can be found with other retailers such as those specialising in electricals.