Random Feelings of Stress and Chest Aching

Every once in a while (I'd guess about once or twice a month) I would have a phase that lasts around an hour or so in which my chest starts aching and my breathing feels shallow. I feel like I have to take a deep breath every 30 seconds or I'll start feeling like I can't breathe. During this time, I feel as if my heart rate accelerates, although it doesn't. My mind is empty and completely blank. Because of this I go back to old habits and attempt to hurt myself to feel something, but I'm able to stop myself before I do. I am just coming out of one now and was wondering what could be the cause of it. The one just now lasted 2 hours and came out of nowhere. I felt like doing everything entertaining but nothing at the same time. My chest really ached this time and at one point, it was unbearable. I'm thinking it's maybe anxiety, but because of my strong mindset, I'm not letting myself succumb to a full attack. I don't know.

i’m sorry you’re going through this. It sounds as though you have some deep underlying anxiety or hurt or depression that is coming out as breathlessness. most likely something is or was going on in your life that has been affecting the way you feel in your mind. The fact that you said your mind is empty and blank makes me suspicious of anxiety and depression which often go hand-in-hand. Sometimes people don’t even know they’re depressed.
hurting your self will not solve anything it will only make matters worse.
My recommendation is that you first get a physical exam at your doctors office just to make sure everything is OK in that department. When everything comes out OK, then you know you’ll have to learn how to manage anxiety and possibly depression .
for the breathlessness you can practice mindfulness breathing exercises which relax the heart rate or pounding feeling and get you in more control. You can find these on YouTube. There is one if you feel kind of panicky that will really relax you and it’s called stop panic attack now. When you find that, scroll down to one called don’t panic in black bold letters. She will guide you through it and it works great!
Another thing that I think is very important is that you speak with a counselor about getting support for anxiety management. It’s very difficult to do alone and it really helps to vent to somebody who can help.
These are just a few things you can do to start feeling better. You deserve to feel better and you can! Be determined. but you do need support. Take care