It's funny, a lot of times when I have an issue I'm dealing with, I check CZ and it "happens" to be being discussed even though it isn't a particularly frequent forum usually.
I first had panic attacks in my 20's, triggered by some mystery virus that I had for a very long time. It felt like the flu and I had fevers for an entire winter. It seemed to attack my nervous system. I lost a lot of weight and got very weak. Then I began having panic attacks, the usual kind with a racing heart, skipped beats and intense fear. I was already married and my son was around 2. I got answers from doctors like "Your a young mom and very busy with a 2 year old, so it is stress." I knew it wasn't that, my son was an easy and fun kid.
What helped me through was this book my parents had (my step-dad got it from his psychiatrist, he was bi-polar)The book was from "Recovery Incorporated" I am not sure if that was its name. Anyway, it said when you feel the symptoms to tell yourself "these symptoms are distressing, but not dangerous." It went on to explain how strong our hearts and vascular system are and how much pressure, etc. they are equipped to withstand, using very good examples, such as the pressure in the arteries and on the heart of weight lifters, etc. Somehow, that information, and the little mantra really helped disarm the fear and they got much easier to handle and then disappeared til recently.
Now I am 52, and they were triggered by taking the sleeping medication Ambien. I stopped after I had taken it for about 4 nights and woke from a sound sleep in the middle of the worst panic amd racing heart, with weakness. It was a lot more incapacitating than the ones I had when I was young.
I am trying various natural things. So far the amino acid Taurine taken on an empty stomach helps me feel more grounded and calm. My favorite way to find supplements is to go to Iherb.com. You can put anxiety in the search box and find several things to try. Then read all of the reviews by people who have ordered and used each product. I just ordered "Theanine Serene with Relora" by Source Naturals. It had 94 reviews, so I really got a good idea of what kind of results people had with it. I haven't received it yet, but I'm hopeful it will help. I just like to read reviews of anything I am ordering. So, you may want to check iherb and see if anything there sounds good to you.--Good Luck!