Welcome!!! I don't know the answer to your first question, sorry... Lucid dreaming is safe for any age... Starting younger might cause you to have better lucid dreaming skills... Lucid dreaming doesn't affect your sleeping... There are many techniques under the WBTB technique... This is when you wake up after 4-6 hours and stay up for a certain amount of time before you go back to sleep... That is where you would be losing your sleep and why you may want to WBTB on the weekends...