If you don't have an oximeter, get one. I recommend a Nonin, but you can get cheaper ones at Walmart or Walgreens. When you're short of breath (sob) check your O2 sats. If they're good (above 90) you're probably air-trapping. You can improve that by using pursed lip breathing. As long as your O2 sats are good, you can keep going for as long as you can stand it. You won't hurt yourself, you'll just be uncomfortable.

Thank you. Hugs to you

It mostly happens to me after an illness. I agree you need to get a Pulseox to keep tabs on your oxygen level. You should discuss this with your pulmonologist as soon as possible.

Thank you so much