I guess the question to answer for yourself is why you find these classes uninteresting and confusing. The fact that you absolutely can't stand it at all is certainly a red flag and cause for concern. You're going to need to learn anatomy and physiology, virology, histology, and a lot of other biologically-based disciplines at a much deeper level than you're getting now. If you can't stand it that much, do you think that you'll be able to even tolerate veterinary school? Moreover, are you going to actually enjoy medicine, where you have to put to work your biological knowledge?
It's hard to tell from what you provided how far along in your academic career you are. It might be time to do some soul searching. If it's uninteresting to you BECAUSE it's confusing, now might be the time to figure out what's confusing about your classes, get tutoring, and fix that. Maybe that'll help. If you want to continue onward and apply for veterinary school, I'd caution that you better be sure that you understand what veterinary medicine, as a career, entails a know that you aren't going to hate it just like you do biology.