What Causes Sudden Breathing Difficulty?

I had a sudden episode of not being able to breath well. It felt like a huge air bubble stuck in my chest. I was gasping for air and it got harder to breath. My husband pounded on my back but still felt like airway was getting tighter. I took a small sip of water and then my airway loosened. I have been real weak since the. I have a history of panic attacks and anxiety. I also have been going through a lot of stress.