3b Student Visa (2 Questions)

Hello, My name is Michael, I come from Toronto Canada and I am currently studying in Nice on exchange. I have 2 questions about the 3b visa and they are a bit specific to my situation so I am having difficulty finding answers on the Consulate website.

1) My 3b student visa expires on December 28th but my flight home is on December 29th. (I booked my flight before I got my visa) Will this be a big issue? Would I have to stay overnight in the Airport? or Should I pay to have my flight moved to the 28th?

2) My second question revolves around the the whole 90/180 day rule. My visa is for 4 months Aug 28th to Dec 28th. My friends want to plan a Trip to travel Europe in January. If I leave France and return to Canada (where I got my visa) will I be able to enter the European Union again as a tourist? It would be after my long stay visa expires. Or should I apply to extend my visa even though I would not be studying anymore?

Any guidance would be appreciated