The holes were caused by the sebum that was inside the blackheads, not by the extraction. Sometimes the opened pore will close back up and sometimes it will not. Try not to put makeup on these, the pores are irritated enough and you don't want the skin to totally lose its ability to snap back. Use an over-the-counter antibiotic cream like Polysporin or Neosporin instead of benzoyl peroxide, and steam your skin to encourage the holes to stay clean on the inside. Drink a lot of water and take a good multi-vitamin. You can try a vitamin B cream too, they are good for your skin.