Hi, so i'm a 20-year-old guy and for a few months, maybe a bit longer, I've been getting hard palpitations, as though my heart is stopping or skipping a beat. I've never had this happen before. This last year I've had a lot of stress and anxiety, as I had a lung collapse earlier this year and although everything "seems" to be fine now, I occasionally get this skip beating feeling sometimes randomly, but mostly when I'm either really stressed or anxious. Also, I realized this has started happening when I do cardio or exercise, it'll occur for a second then go away. It just really scares me that it could be something more. About 6 months ago I had a lot of x-rays, blood work, and a physical because I had severe anxiety due to small health problems and my collapsed lung that is fine now. I have really bad stress and anxiety, acid reflux, post nasal drip, depression, and a few other minor issues. other than that, well according to my doctors I'm healthy. So what I'm wondering is what these heart palpitations are? And why did they suddenly creep up on me recently? I know they can be caused by stress, but sometimes I'm not doing anything and they can happen, it especially worries me when it happens as I work out. I'm really young so hopefully, it's nothing serious like heart disease or other heart-related issues. What's your opinion on this? I'd rather get a first opinion instead of seeing my doctor again for the like 12th time this year, thanks.