Do not worry. You are fine.
Under the new regulation, for programs that are shorter than 6 months, you do
not need a study permit.
From http://www.cic.gc.ca/english/study/permit-who.html
If you wish to study in a short-term course or program:
You do not need a Study Permit if you are planning to take a course or program
in Canada with a duration of six months or less. You must complete the course
or program within the period authorized for your stay in Canada.