Be patient with yourself. As a student your job is to learn, and by necessity, fail. Solving the problem and having the right answer isn't always the same thing.
Do your research: on the lab, on the faculty, on the department and on the city itself. There are so many different programs/departments and it's imperative you know what you're getting into. Speak to students that are currently in the lab or have recently graduated to get an idea of how things work. There are going to be some tough times in your program and you want to make sure you're surrounded by people that want to support you and help you get through, to be successful.
To any undergraduate student that wants to pursue graduate school, my best advice would be to study hard, celebrate your academic victories, and don't get caught up on your failures. Everybody has a story of a course they wish they did better in, or a midterm/exam that was an unexpected curveball, but as long as you learn from your past and keep pushing forward, things will work out for the better.
Guelph will provide you with a supportive and stimulating academic environment. My advisors provided me with the freedom to explore my research interests and the support and mentorship to help me become a better scientist. Their positive attitudes and confidence in my abilities allowed me to achieve success in my research goals. There are loads of clubs one could join (e.g. qualitative journal club, welfare and behavior group, dairy journal club, graduate student social committees, art clubs, etc.). In addition, my graduate program provided me with a safe and interactive social environment (e.g. intramural sports, city leagues, department socials).
For my non-native English-speaking friends, there is a plethora of support from the international office! In addition, the library provides lots of writing and technical support!
I would encourage all prospective graduate students to research their program of interest and speak directly to faculty prior to applying as this can ensure that your research goals align with your prospective advisor/program of choice.
Smart or slow, doesn't really matter in the end, the point is everyone has their own time zone, all you have to have is your own balance of work, play, and all other stuff, the others don't really matter.
I recommend taking the time to thoroughly research potential graduate programs and supervisors to find one that is a great fit. It is important to work with a supervisor whose interests align with your own, as passion for your research will help you succeed in academia, especially when things get tough! If you are passionate about reproductive health and fertility, I wholeheartedly recommend the MBS program.