Hey Amet. I started struggling with this same exact problem when I was about 17. I'm not entirely sure of what caused it, but one day I just noticed that it was getting harder to breathe and I had convinced myself I wasn't able to breathe. Of course at the time I did not know this was a symptom of panic, so I had my friends drive me to the hospital where they X-rayed my chest and told me everything was fine(They actually told me I was hypokalemic at the time but I'm not sure that had much to do with my panic). It was one of the most terrifying experiences of my life, so much so that I had begun to worry about it a lot. I had no idea what my problem was, I would search around online for hours trying to figure out why I would feel like this out of the blue. Even the next couple of days after that first experience while I was at home, I felt it again and I had my father drive me to the ER, this time they took some blood and told me everything was fine again. Eventually I figured out that what was happening was that I was having panic attacks, and I was constantly afraid of feeling that same awful feeling of that first full-blown attack. For a long time, I became very depressed and stopped enjoying the things I used to love. I started avoiding my friends that were around me when the first attack happened, and holed myself into my room for as long as I could every day. I eventually dropped out of school because I couldn't handle the daily anxiety attacks I had at that time. I eventually started to miss the things I used to like so badly that I just went out and did them anyway, consequences of my agoraphobia be damned. Even at that time I did not have the useful resources I do now to help me manage my anxiety but doing that over and over eventually made me feel very calmed, I was able to convince myself that nothing bad was ever happening when I did the things that triggered my anxiety attacks and that I was always safe, and that nothing was wrong with my breathing. It took sometime less than a year to fully get myself back in control. I'm almost 21 now, but last month I began to have anxiety attacks again. The first time it happened it was quite severe, but I thought nothing of it even though I felt very worn the rest of the day, and I felt fine the following day. A month later however, it happened once again, but this time I felt very confused as to why this would happen to me again. I began to slip back into the pattern of daily panic attacks and dreading the next one after each one passed, hoping they would end or just go away. I started obsessing over my breathing and not being able to get it under control, as I thought losing control of my breathing started my panic attacks or at least made them worse. During my series of panic attacks when I was 17, I had read that measuring your breaths out using that old 7-11 trick was a way to restore a normal breathing rhythm in the case of a panic attack. I did this anytime I started feeling anxious (with a stopwatch handy), though sometimes when I got too anxious, I felt like it wasn't working and it made me panic even more, and breathing seemed to get harder and harder. At some point I began to obsess over time. Sometimes when I get anxious I will check the time, and I will become very concious of how my I've been breathing since I last checked. So if I start feeling anxious, I begin to think I must have been breathing out of that 7-11 rhythm and would immediately try to fix it. I would be concerned that it might not make me feel more relaxed so I would just start getting more anxious about it, and eventually it would feel too difficult to hold my breath for longer than 10 seconds. However since I know all about what this experience feels like, I know for sure that with practice and perhaps some meditation and other relaxation methods, that this feeling dissipates and I won't have to fear my fear anymore. I've been using this program for about a month and I already feel remarkably substantial changes from how I felt when this started again. I'm very glad I have access to the resources and support I do now and I'm confident that with these things I can get over my anxiety in a fraction of the time it took before. I can begin to enjoy the things I always did after I reteach myself how to react to my worries. It's a long road and fighting anxiety is not easy but it can be done. Stay strong and we'll all find a way through this!