I sympathise with you. I can identify with everything that you are saying right down to the allergy fear. It started for me as post natal depression when I was 22 and peaked through my late 20’s to late 30’s. I am now in the later half of 40’s so hope that I can give you some advice.
I learned to accept that I suffer from anxiety disorder and that I was a highly sensitive individual. I am hyper sensitive to environmental changes, fluctuations in temperature and my body reacts strongly when there is an insulin or hormone imbalance.
Once I accepted this (and it took 20 years to recognise)’ I started to work with the issues. I struggled with panic attacks for so long that they no longer presented as the typical hyperventilating for a brief period and instead began presenting and a feeling of doom, a completely overwhelming fear of not having control. They would last all day and the pain attached to them was so bad. Chest pains were very painful and physical which convinced me I was having a heart attack.
Once I began working with my anxiety, the pain subsided as I wasn’t trying to battle my bodies warning system.
And that is exactly what anxiety is. It is your bodies warning system that something is affecting you on a deeper subconscious level. Now think about it this way, you are someone who is able to recognise anxiety as you are so sensitive to it. This means that you probably don’t store stress in the body as much actually making you less likely to have stress related heart problems.
So now, when I feel that impending doom or general feeling of breathlessness or pain, I journal and spend time working out what my body is telling me that I need to do. Once I have named the worry and recognised that is is having a physical effect on me, the anxiety leave since I have bought the fear to my consciousness. It is like my body says “okay, I can turn the alert system off now because it has done its job”.
I hope this helps. I still have anxiety and I suspect I always will but I frame it as being a highly sensitive person. I appreciate that my body is able to warn me when my emotional balance is out of whack and I am inspired to act upon it.