Here's the hammer on the head; you don't smoke at all until after your Class 1 now you should be fine. You smoke after your Class 1 and don't expect to be as efficient a learner in your flight training. Unless you are daddy's rich kid this is a once in a lifetime chance to prove yourself aviation worthy, and as a pilot you must learn to assume responsibility for yourself and your actions, and that includes smoking gange. C'mon mate, pull yourself together and realise what a career you're taking on.
