If you joined and have a tube, then when it's flattened out, the knits will be on both 'sides'. You should have knits on the outside of the tube and purls (the bumps) on the inside. Maybe you just need to work a few more inches.
The only way to get knits on both sides is to knit a tube like you're doing, or double knitting which creates a closed tube. You can also do k1 p1 ribbing and it draws together so it looks like knits on both sides.
sue- knitting heretic