A degree in biochemistry would be a Bachelors of Science degree. Biochemistry is your major or specification within the Bachelors of Science. So, when you complete your undergraduate education, you will be receiving a Bachelors of Science in Biochemistry. Unless you are currently in a program which is not actually for a Bachelor's degree, like an associates degree for example.
How long the application takes is really dependent on the individual. The application consists of entering your grades, entering your optometric experiences, as well as other work experience and extra-curriculars. Your letters of recommendation (from optometrists and professors) will also be done through the OptomCAS application. The part of the application that takes the longest is the essay/personal statement. The essay is actually quite short, but it personally took me a while to get it exactly the way I wanted before submitting. In order for your application to be complete, you will also need to arrange to have official transcripts from your school sent to OptomCAS so they can verify your grades and this can take some time because it is done through snail mail. Another component of the application system that takes some time is the supplemental applications that are specific to the schools that you are applying to, and many times those involve writing additional essays. For some people, this process may only take a couple weeks, for others a couple months.
I did not apply to Waterloo, although in hindsight, I feel like I probably should have. It is definitely very competitive, but depending on your stats, that doesn't mean you don't have a shot. If you are applying to Waterloo, keep in mind that their application process is very different and they have many deadlines that you have to keep on top of, including when you need to have written the OAT by! I know Waterloo wants you to have 5 classes every semester, but I'm not sure about the US schools. I don't think 4 classes a semester should be a problem because it is still the course load of a full-time student. There were a couple semesters where I only took 4 classes, and there was one semester where I only had 2 (I had to withdraw from a few courses for medical reasons), and that didn't seem to be a problem at the schools I interviewed at/was accepted to. To be sure, I recommend that you call the schools you are interested in applying to, and ask them whether 4 courses per semester is good, or whether they prefer 5.
In terms of shadowing at a clinic more than once, it really depends on the clinic. The doctors at one of the clinics I worked at were more than happy to let me shadow and volunteer a few times, but at another clinic the doctor only wanted me to shadow for an hour! I think it depends on how busy the clinic is in terms of appointments. I've actually been working a clinic for almost a year now, which has been an amazing experience for me because it is so hands on! The doctors and the rest of the staff teach me so much to prep for optometry school! I think volunteering in an opthalmology clinic will definitely be valuable, but make sure that you do the same with optometrists as well. The reason I say this is that some schools require certain amounts of shadowing with optometrists, and opthalmology clinics do not count towards that. Also keep in mind that some schools require certain amounts of unpaid optometric experience (for example, Pacific requires 30).
And yes, most schools start interviewing as applications come in (rolling admissions), therefore it is best to get your application submitted earlier in the cycle when there are more seats available. I believe Berkley, and perhaps SCCO, don't do interviews until later in the cycle.
I hope that helps! It was probably a lot more information than you needed/wanted lol
