Thanks for posting on MacInsiders, Faith!
Not sure who you spoke with in the Soc Sci department, but it sounds like they gave you bad advice. Did you speak with an academic advisor?
Saying it's not a 'big deal' to drop courses, doesn't make much sense to me. You need to take the required amount of courses, as you correctly pointed out.
https://socialsciences.mcmast er.ca...oming-students
30 units:
Required: 18 units of Social Sciences
Electives: 12 units of courses of your choosing which may include Social Sciences
So you'll want to look at taking summer courses to make up for the dropped electives so you can get 30 units. You won't be able to enter Level II until you complete Level I with the 30 units.
If you dropped the 2 classes early on in September, you may be eligible for a refund or some money back. Might want to talk with the Registrar about that.
Goodluck!