Can't breathe this slow even if I try. I normally breathe 30 times a minute.
You may want to focus on where you are breathing in your body. I have a very slow breath rate and super slow hear-rate, so 4 seconds is painfully fast for me. I'm about 8-10 seconds in or out and a comfortable 6 or so seconds rest between breaths.
To breath quickly, I have to focus on breathing only in my upper chest. You may have been trained to do this over-time, and feel very normal doing it.
Watch a child breathing, and you'll see they breath deeply into their belly. This is the natural breathe you want to aim for.
If you've been breathing into your chest for ever, your lower lungs are likely going too be tight, and it will be very difficult for you to expand and breathe into them. But it's worth trying.
When you lie down, try relaxing and try to relax your stomach and let it rise and fall with each breath. It takes re-training your diaphragm.
Where I do agree with the other comments here is that you likely should decrease your breath rate as it is better for you, as long as there is a good reason for you to be breathing as quickly as you currently are.
What are the symptoms of that? I'm almost 40 and never had any health issues so far. The breaths are shallow but I'm surprised to hear my breathing is abnormal so I should probably speak to a doctor.
So, quite possibly nothing, or nothing you'd realize. Bodies are adept at compensating. But there are potential concerns, and also, a chronic (and compensated for) issue can acutely deteriorate.
I am not a doctor, though.
[0] https://www.merckmanuals.com/professional/endocrine-and-meta...
The body goes to extremes to keep blood chemistry within a very narrow pH range. In practical terms, this means that your body strips your bones of calcium if your blood is chronically too acid because you die rather rapidly if your blood gets too acid.
You might find it worthwhile to read up on altitude sickness and what happens in the body at elevation. When you cannot breath out wastes efficiently because the air is too thin, the body copes with the chemical derangement of your blood by dumping it out the kidneys. This has knock-on effects, like dragging other stuff with it, especially fluids and electrolytes.
I'm healthy overall and really surprised that my breathing is considered so abnormal.
I assume you're able to do decent amounts of exercise and don't find yourself out of breath when doing regular things like going for a walk or going upstairs?