/biz/ - Business & Finance

I'm 28 and until this year I had no credit and I was happy with that because I also had no debt.
Then I crashed my car, had to get a new one and got hit with a 21% APR.
I had some unpaid hospital bills that just today finally fell off.

When should I refinance my car loan? I know it will add to the length of my loan so I'd like to do it sooner than later, I also know 620 isnt that great.. but $375/mo is killing me.
Are credit cards a scam? Because they feel like a scam..
Also general tips about credit would be appreciated, I'm tired of living with my parents.