well if you have abs you need to bleed from the closest to the abs unit to the furthest away.... if you don't have abs you bleed from the furthest away from the brake master cylinder to the closest to it.

and if you did that, then it sounds like your master cylinder is bad.

but more likely you bled improperly....and sorry but why did you bleed the brakes when you changed them?

EDIT: Also, if you took apart your calipers, you may want to look and see if you are leaking from your crush washers, if you didn't get new ones.