Not sure

I was having shortness of breath last week so I went to the ER. I was there for 6 hours. They did a EKG a chest x -Ray with & without contrast. They also did a CT scan of my heart .Every test came back normal. I have a colonoscopy coming up next week plus a Endoscopy. I have Gerd which makes it hard to swallow food .They will try to widen my throat so I can swallow easier. I was diagnosed with mild COPD 6 years ago. I quit smoking the next day & have not smokes since . I used an inhaler & a nebulizer for about a year or so & I was able to stop both. I went for a follow up 3 years ago & my numbers were ok but not great. I told him my breathing was normal so I have not used anything for 3 years. I have bad allergies & this is a bad season for allergies so I am hoping that is the problem.I did the 6 minute brisk walk twice. I started at 98 oxygen & finishe at 98 oxygen. I did the walk again the next day & started at 98 & finished at 97. All this being said hopefully I will have answers next week. I will keep you posted on my situation. Thanks for letting me ramble . BIg B