Need to pay medical bills but don't have any money and can't work currently

earlier this month I got in an ambulance just to check my heart rate and it was over 170, but that usually happens with anxiety and I was feeling just fine, I thought I would be able to leave but they insisted on taking me to the hospital which ended up for me to pay for the ambulance ride. it's a lot of money which I don't have. I'm already looking for things to sell. Any advice is much appreciated thank you.