In Act II Scene 2 Juliet says I have no joy of this contract to-night it is too rash unadvised sudden like lightning which doth cease to be. Why does she say this?

In Act 2, Scene 2, Juliet is expressing her conflicted feelings about her secret marriage to Romeo. She says she has "no joy" in it because it feels too rushed and impulsive, like a fleeting moment that quickly passes. She worries that their hasty decision might have been reckless, and she feels a sense of uncertainty and doubt about the future. Romeo, on the other hand, is more optimistic and assures her that their love will overcome any obstacles.