No problem, I think it was important to write it out so you can frame where you stand and what your options are. Most members here are just as supportive, I simply elaborated on what others have already mentioned.
I am afraid you still don't fully understand your situation. You mentioned that you've only thought about this in your final year, and you have a lot of research to do.
A few points of clarity for you: without a second undergrad or more years of full time study in undergrad (minimum 2), your chances are near 0% right now. So when you apply, you need to have 2 full years of grades already. If you started sept 2020, you need your grades from 09/20-05/21 and 09/21-05/22. Effectively, your chances won't be significant until Sept of 2022, which is 3 years from today. A MSc won't help you, Queen's Western and Dal only care about undergraduate grades, most grades from the MSc don't count towards med GPA calculations.
Like others have previously mentioned, your academic record would almost exclude you from the entirety of the US, UK and Australia.If you look at the overseas list that accepts Canadians, you'll come to a realization that all of them are 3.5 and above(and that's really stretching it). You need to sit down, do some research on the statistics and cutoffs. I think you are overly optimistic about your situation, there are less than 30 medical schools that frequently intake Canadians. Not a single one of them will accept anyone with a below 3.0 GPA international student. Spots in the US are very limited for internationals as they typically favour their in-state students. A second undergrad is a huge red flag during their application process, their ADCOMs are not as forgiving as Canadian school ones. The practice of doing a masters and applying again is different in the US, as some schoo's have their own MSc program to specifically help people get into their affiliated medical school program. Most student serious about research goes directly into a PhD in the states, so the evaluation of a Canadian MSc is tricky. The Caribbean comes with enormous amounts of issues on its own, a quick search on r/premed or these forums would lead to the logical decision not to do it. If you truly value staying near your support system, I find it difficult to believe that you are unwilling to move provinces but willing to cross entire borders.
Finally, yes, it is daunting to be taking classes with people who are much younger than you, I've done it, it sucks. You feel like you don't belong there. But you have to make the most tactical and necessary decision.
Best of luck to which ever path you have chosen,