You have the symptoms of the heart not get a sufficient supply of oxygenated blood. The feeling of suffocation is an indication there may be congested heart failure. This heart failure the blood backs up into lungs and fluids leak into the tissues. Often there is a dry cough, shortness of breath, hyperventalating and feeling of smothering. That alone can get you into the ER. That was my experience, and I was diagnosed with congested heart failure.
As suggested you should go to emergency even if the symptoms go away because there could have been heart damage with the event associated with your symptoms and there is treatment.
Hope this helps, and if you have any follow up questions or comments, you are welcome to respond. take care
You might be having a heart attack. Please call 9-1-1 or your local emergency number if not in the U.S.A. for an ambulance!