How much do mechanics make at pep boys?

I started out as a mechanic at pepboys about six months ago. I went to school for hvac, but I've worked in garages my whole life as a mechanic. I am currently 21. Even with all my experience in Auto and no certifications...I started out at $15 an hour. But its alot of work for $15 a hour and alot of hours...a typical day for me is from 7am-7pm. Monday-Friday. Then 7am-4pm on Saturday. Its hard on the body but you make your money in overtime...thats all.