Is there any such thing as a "mild" panic attack?

Not seeking medical advice; this has been going on for years and years and I don’t think it’s any threat to me.

I’ve heard about what it’s like to have a panic attack and that you feel like you’re dying and your breathing is completely out of control, etc. I’ve never experienced that.

However, since I was about 13 I have periodically had an issue with feeling that my lungs aren’t filling to capacity. I’m still getting enough air but it doesn’t feel satisfying. It feels like the air isn’t getting down into the bottom of my lungs or something; I tend to yawn a lot to try and compensate.

It has been going on for ages and has never been a big problem, so I’m not worried, but I’m still curious what it could be. I’ve read a bit about mild asthma and it sounds possible. Other suggestions say it could be related to anxiety, though, which is something I do know I have a problem with.

Is there any kind of milder form of the classic panic attack you usually hear about?