Help a under educated 20yo!!

So I recently switched employers due to manufacturing and management issues. I did voluntarily quit on September 23rd, but I had another job lined up for the upcoming weeks. Upon starting my new job, I applied for the insurance and chose the 60/40 plan (autonation) But during all the swapping and changes, on October 21st I had a spontaneous phenoumthorax leaving me in the hospital for 2 days and a ambulance ride. Come to find out, my new health insurance doesn’t kick in till the 1st of November. So from the 23rd all the way till now I’ve been uninsured. Now I have a 15k bill on my lap. To be completely honest, im not educated on this matter. I have had a laser focus on law for the past few months regarding my last employer and haven’t really looked into health insurance and how it works etc. As a 20yo with no a lot of help, I feel lost and like I’ve been given the finger by anyone I consider asking questions. Just trying to figure out the best case for this, I know I can just pay them x amount for the rest of my life but I still don’t want medical debt sp I don’t know what to do in this situation, the bill is 25% of my yearly gross income so I can’t justify paying it off in full within the next 2 years like the payment plan suggest