This app was mentioned in 4 comments, with an average of 1.50 upvotes
I can relate. Last year I had 4 ER visits and so far this year I've had 2 visits. I take my backpack with me everywhere. It holds my epi-pen, two different inhalers, prednisone, and allergy meds and sometimes my nebulizer.
The idea of being attacked by someone is my biggest fear. Because my asthma has become so severe that I have less than a minute of activity before I'm unable to breathe at all. This completely changes my mindset about danger. In the past I was perfectly content with the idea of defending myself in the event of some sort of attack, but now any type of attack is immediately life threatening for me. That means that it's now literally kill or be killed.
You might consider the Cradar app. You activate it when you are heading out and if there is no movement for a set period of time it will send a text message to a designated number and send your GPS coordinates. It also gives you a notification before it sends the text so you can let it know if your lack of movement is intentional. It's designed for motorcyclists, bikers, and hikers, but I'm pretty sure it would also work for you.
looks kinda useless and sketchy IMO. If you're looking for that functionality, check out CRADAR. It's a free app and lets you abort an alert if there's a false crash detection. https://play.google.com/store/apps/details?id=actionxl.mandown&hl=en
No special helmet needed, I've been using the CRADAR app for years as a 'man down' notification:
https://play.google.com/store/apps/details?id=actionxl.mandown&hl=en