@gabrielm I have the same condition and I've had it for over 5 years as well. I went to a doctor in 2015 who made me get an x-ray and do a lung test in one of those big boxes - they ask you to breathe as deeply as you can etc and measure your lung capacity and health. The doc told me that my lungs are getting sufficient air, so I mustn't get anxious over this condition. Anyway the condition disappeared for over a year for me as well and then returned. I still can't figure it out, when I am actively thinking about my breathing and take a deep breath, it stops right before it satisfies me. I have to take 10 deep breaths sometimes to finally get one that 'goes all the way' (no one understands me trying to explain this, but I know you will), and even then, the relief only last a few seconds before I feel the need to take another one. At other times of the day sometimes I don't even notice I have a problem until suddenly i feel the shortness of breath and focus on it, then I just feel terrible.

I also don't have other medical conditions.