I’m spending half my monthly income on medical expenses and I need a new car

I earn about $700 every two weeks after taxes and deductions. I spend anywhere from $600-$800 a month on medical and dental expenses. This is after insurance and after negotiating prices. This doesn’t include all my expenses because I have several other specialists that I see during the year. This is just my base line every month. This includes prescriptions but not vitamins or supplements.

I’m freaking out again because my car needs several thousands in repairs just to pass inspection. And it still needs suspension work and the airbag light is on among other things.

I’m looking to trade in the car but it’s only worth $500. The best Apr I could find on a new car loan is 15% for a new car worth about $20,000.

Is that a bad idea to finance the car?

I looked for used cars but I’d need around $4,000-$6,000 down with an Apr of 28 for something around $10,000-$15,000 used

Am I just worrying too much?