If I were you, I'd do extra exercises....

EXERCISES FROM THE INTERNET:

http://www.ego4u.com/en/cram-up/tests/conditional-sentences-3

http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/cat-and-mouse

http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/cat-and-mouse?02

http://wwwedu.ge.ch/cptic/prospective/projets/anglais/exercises/condit4.htm