I had this happen a few years ago, and my husband rushed me to the ER. They did tests, but turns out it was acid reflux that was coming up, and keeping me from getting air. I have since been on a pill for this.
Hope this helps you.
Sjogren's, Lupus, Hypothyroid, Fibro, Sleep Apnea, diabetes, asthma, Polycystic ovaries, and Gerd. Meds - Pilocarpine, Synthroid, Effexor, Cpap, aspirin, Prilosec, Neurontin, Xanax, eye Drops, vitamin D3, Plaquenil, Gabapentin, Provigil , Advair, Proventil- Retired Teacher/Disabled