ok so i just finished my exams at my high school a few days ago.
before the exams i studied heaps hard sometimes 4-5hrs at a time and up till late at night.
within those 2 weeks of exam period i had 3 lucid dreams. i forgot to mention that i have NEVER had lucid dreams before that i can recall and ive been trying for months now. i also may add that during that time i didnt think much of lucid dreaming.
so these 3 lucid dreams were the first ive ever had, i have a few questions:

1) does this happen to others? or is this possibly just a 1 off case?
2) why now? i mean is it because of my studies or change in daily habits?
3) is there a way use that experience so that i may have future LDs? eg study more?

thanks any help will be appreciated