How much $ do you have in the materials? Fabric,Batting and thread? how long did it take you to make them? Cutting, piecing, layering, quilting, squaring, binding? If you subract the costs of the materials from what you are charging, are you happy with your hourly rate?
If you do a search on this board, there are lots of topics which include suggested calculations.
Having said all that, the prices you quoted seem in line to me.