Feel free to PM me, but I'll reply here for others if they are interested. My daughter was 17 when she caught it, started with a serious chest pain, uncomfortable pins and needles that stop you sleeping at night, headaches, brain fog and fatigue. No breathing issues though. Symptoms would often cycle and you wouldn't get all of them at once. In the summer there were green shots of recovery but it was short lived and all the symptoms are back just as bad except for the chest pain which though still bad is not as excruciating as before.
She had picked up other symptoms too, like loss of smell and taste, etc. Again the symptoms cycle. Went to the hospital in September (cases were very low then so a good time), blood tests, x-ray, etc, done but as expected found nothing. I have spent most of my time on a Long Covid Slack group which I would advise for you to join.
Sorry to hear about your symptoms. It's bad enough to get it in middle age but to affect you in the prime of your life is depressing. Main thing is to reach out to others in your boat, we need to get through this mentally rather than physically, and medical professionals are not currently equipped for that. I've had a few shouting matches with three of my GP footy mates who are still in symptoms denial stages.