Yes you did it correctly! Just remember that after you do (3dc, ch1,3dc), you have to do
"skip next dc, work 3 dcís in next dc, ch 1, work (3 dcís in next space, ch 1) twice, ch 1] around.
Join to top chain of beginning chain 3. ~ 12 dc groups " , to finish to round.
It should be a bit ruffled as you are increasing the number of stitches.
Keep it up and let us know if you need any more help.