Is this serious or is it just a normal thing bodies do?

Meamdmyself
I had this pain in my left chest that goes to the left upper abdomen and kinda in my left side of the back. It hurts more when I try to breathe.

I know it's normal to feel something like this sometimes, especially as a teen, but it's just annoying and it hurts bad enough to make me think just about it.

I feel like my pancreas hurts but also my heart and just the overall left side. It's been hurting since morning. It's nearly 12 pm now. It like comes and goes but at the same time it's always there. Like it just changes intensities.

When I was at school it was pretty bad, like I had trouble breathing (it's pretty normal for me, especially somewhere with lots of people since there is less oxygen). It felt weird breathing, like I was inhaling hot air when the air was actually normal. Also I had some floaters today. But I checked my bp and it was either 100/70 or 110/60 so I don't think it was because of my bp.

Anyway, this pain is really worrying me. I feel like my health just gets worse everyday. The second I think it stopped, it would actually get worse. I feel really tired and my head hurts.

At school, I had a tension headache that also kinda got to my neck and the back of my head. It's not fun at all. I also get dizzy and lightheaded when I walk up the stairs. I talked with a friend and she also gets lightheaded, but it's cause she has a high bp, but I have never had a bp higher than 110/70 that I know of. I thought I might have orthostatic hypotension but I don't know if that's the case.

It's kinda funny that I started talking about my chest pain and ended up with my bp. Anyway, is there anyone knowing why this is happening? I tried doing research but everything says that it might be pancreatitis, GERD or other disease.

Also, this is not because of anxiety. I'm about 90% sure it will go tomorrow and I hope it never comes back.
Updates
7 mo
I told my mom. She is worried but at the same time says it's because of my phone. I can understand where she's coming from, but c'mon. Anyway, I don't think I'll got to hospital cause now I feel a bit better. I mean I still have pain in my chest when I breathe, but it's not as bad as yesterday.
Is this serious or is it just a normal thing bodies do?
4 Opinion