CREATE TABLE table_name_68 (date VARCHAR, opponent VARCHAR, week VARCHAR, game_site VARCHAR)

When did the Titans play the Houston Texans at LP Field before Week 13?
SELECT date FROM table_name_68 WHERE week < 13 AND game_site = "lp field" AND opponent = "houston texans"
SELECT "date" FROM "table_name_68" WHERE "game_site" = "lp field" AND "houston texans" = "opponent" AND "week" < 13