Persistent Chest Heaviness/Tightness

Hello,

I am a 25 y/o male and I began experiencing chest tightness/heaviness around the sternum area, more so the bottom of it, since March 2024. This is a sensation that never goes away and is persistent throughout the day the moment I wake up. My PCP doesn't seem to know what it is as we've exhausted a lot of possibilities.

What's been done:
- 3 X-rays, 3 EKGs (they look normal, done at an Urgent care, ER, and PCP)
- Oral steroids (no effect)
- Allergy testing (nothing found)
- MRI chest scan (nothing found)
- 2400mg of ibuprofen daily, 30 days (no effect, prescribed by a 2nd opinion doc). Not much luck with Tylenol either.
- Upper endoscopy (no issues found), did 40mg of omeprazole for months with no improvement while following GERD diet.
- Cardiologist found no issues so far, though will follow up later for a stress test to see anything else can be found.
- Physical Therapy, working on trying to get a referral to continue this.

What seems to work:
- Doing core exercises alleviates me of the sensation as well as long as I keep doing them. After I stop, the feeling comes back though.
- Urgent Care gave me a steroid injection, which alleviated the issue for a week. It then came back afterwards.
- Muscle relaxants seemed to work before, though I don't know if my tolerance went up as they don't work as effectively before
- Applying slight pressure anywhere on front chest immediately alleviates the feeling as long as the pressure is there. I've been wearing a chest binder in order to be relieved of this feeling. Though the sensation immediately comes back after taking off the chest binder.

I've talked to a 3rd doctor about this to get another opinion on this, to which they suggested it's musculoskeletal probably. But from there, I don't know what else they can check in this area. Please help, thank you.