Grieve, mourn and wail. Change your laughter to mourning and your joy to gloom. (NIV)
[As you draw near to God] be deeply penitent and grieve, even weep [over your disloyalty]. Let your laughter be turned to grief and your mirth to dejection and heartfelt shame [for your sins]. (AMP)
Be afflicted, and mourn, and weep: let your laughter be turned to mourning, and your joy to heaviness. (KJV)