What Causes Dizziness And Heavy Chest With Normal EKG?

Question : Hi. I was on a plane flight and was awakened from a nice sleep suddenly with incredible pressure in my chest. I felt we had dropped altitude. My husband didn't feel it. It got harder to breath. I couldn't hear. My ears clogged. Everything got foggy with my vision. Flight attendant rushed with O2. A dr on the plane came to my side. I passed out for a few secs and came to breathless and fatigued and couldn't think. Landed and paramedics checked he out. EKG and o2 and bp. All normal. Heart rate 56-62 and back and forth. I followed up with PCM. Everything so far normal except low heart rate still at rest. Had X-ray. Heart structure looks normal. Had head CT normal. I had another episode today after dropping off my daughter at an activity. Just getting back in the car. No fainting. But dizzy and heavy chest. Went to Urgent care just on the corner. EKG normal. He thought he heard an early beat here and there but after the EKG he listened again. Nothing. I feel this full ache in my chest all the time since the plane incident. And occasionally my ears will clog up like I can't hear as well but not as bad as on the plane before fainting. I'm scheduled for cardiology next week for a halter. I'm 41. I have never had a heart issue. I had day surgery in summer and nothing ever picked up on EKG then. Had Orthopaedic surgery last year. No issues then. I feel
A bit week and like I'm aware of my heart all the time now bc it feels different. I'm fearful this is the beginning of a sick sinus syndrome or a chronic brachycardia. Or maybe mitral valve prolapse. Something along those lines. Why does the pressure change cause such a feeling of heaviness. I felt it just before it rained too this week. I have never had panic attacks or any other issue like that. I also think and almost feel a gurgle in my heart. Every minute or so I feel a gurgle. It almost sounds like a growling stomach. But the dr didn't hear it today.

Thank you. I have a syrinx in my spine T2-T8 that we think was acute onset in 2009. Caused so much pain all around my ribs and took several years to get through with PT, tens unit etc. I had cervical stenosis too. Take Celebrex for overall pain, neurontin for spasms etc and for a long time had XXXXXXX as needed at night for back pain and muscle spasms. I have stopped the XXXXXXX since this started and over the last day or so stopped my neurontin. Could celebrex be a culprit to all this?