I believe that there are days that are actually cursed. Both Job (Job 3:8) and Jeremiah (Jeremiah 20:14) prayed to God to curse some days. Whether it was 9/11 or Friday the 13th, I don't know.
Mark you, those who are believers are not subject to such curses as delivery from those curses comes from acceptance of the covenant with Christ.
Also, death and life are in the power of the tongue (Proverbs 18:21). Some Old Testament fathers cursed their children, grand children like Noah ( ) or Jacob (Genesis 49:1-7). I do not think that Job's and Jeremiah's words fell to the ground.