For schools such as Queens, Western & Dalhousie they only consider your final two years of GPA for entry. Western requires a 3.7 gpa cut off in both years as long as the courses taken are 60% at or above course level (like taking at least 3 third year courses each term). As long as you work really really hard for the next two years or 3 (which by the way, Ottawa considers only last 3 years) there is absolutely no reason why you should give up on medicine. Take a good look at these schools to ensure you meet their requirements, and be careful not to make yourself ineligible for the weighted gpa options of other schools where they might drop your lowest courses or your lowest year.
Overall advice, look at ALL requirements of Canadian medical schools, but you can most definitely still get into medical school if you have a great gpa these next 2-3 years. Also study really hard for the MCAT and prep hard for the CASPer, get your ECs ready and don't give up hope. You can definitely do this.