Why did you want to go into commerce in the first place? Surely, there must have been an original reason you chose it over science and biomed. I think this is important.
Throughout uni many of us get exposed to things we've never learned before or start thinking about other options. We all have our "grass is greener on the otherside" moments and yet most of us stay where we are. I know myself i've contemplated swapping into arts or something commercy a few times (ontop of other things).
I know it might sound a bit harsh but you have to seriously think if this is just a desire on a whim, the grass is greener or if it is actually a serious, well thought out and planned decision too.
Is it just me or has anyone actually ever felt bad about their course decision but got over it??? I don't know if I'm feeling bad just now but I sort of don't want to act until it's too late...
In uni its never
too late. People take various lengths of time to complete their degree. Some go part time, some fail subjects, some go overseas on exchange, some swap majors, etc. Even at UoM people can pick up diplomas and things like that which will also alter the length of their degree, no one will really care if you take a bit longer.
Now, at the same time, i'm not encouraging you to go down with a sinking ship. If you know its bad/you absolutely hate it and you've had enough time to recognise it, i would say jump ship. Right now though, i'd tell you to wait it out. You obviously went into commerce with some reason and desire behind it. You've only been at uni for maybe 4 weeks. You've only done maybe 1/3 of your subjects and only four subjects at that. It isn't a very good sample to gauge it off. I dont know if you'll take my advice or not but its worth giving, i reckon you should give it another semester and transfer at the end of the year if its still horrible.