Breathing gets worse at night and breath gets cut off sometimes

[Amesketches]

Hey so I already made a question on this, I had thought this was my heart but I realized it may be my breath, it's kind of hard to decipher what it is though.
So I will start with the general, I have this strange thing where I have a shortness of breath. It feels like I can't get enough air or something heavy is on my chest. Most of the time it happens in the mornings and at nighttime, but it can happen in the afternoon, sometimes for even the entire day. This does not affect me to do anything other than bringing me discomfort while I try to sleep. When I exercise it seems I forget about it. But the thing that worries me is that sometimes while I'm laying down or walking, I feel right in the middle of my chest as my breathing gets cut off for a second. It's really fast and I always get surprised by it. It almost feels as if something shakes. What I realized is that this can happen when an breath a lot. An example would be I was running laps in my gym class and I was breathless of course after running, but when I took a breath that thing happened to my chest. Another example would be that once I was crying because I got hurt (and when you cry you usually take in breaths) and it happened again.
We went and got an X-ray for my lungs and they said everything is fine. We also went to the doctor and he told us that he can't really give a solid diagnosis and that as long as it's not affecting my daily life then it's fine, and my parents should just watch over me for any new symptoms and such. He also said it's very unlikely it is asthma.
I guess the reason why I'm asking this site even after I got a diagnosis from a doctor is that I'm not sure if I covered on the cut off of breaths that well, so I'm worried he may not have heard or something.
I'm a 13 year old female, thank you for reading.