YOu can try Lippincott's BIochem,but seriously speaking, that book's pretty text heavy but it also contains lotsa pics ie.diagrams as well, which are pretty helpful because learning biochem for me is easier with diagrams. Diagrams help you interrelate the different cycles and once you get it, you'll notice that alot of chains are interrelated.
After you finish Lippincotts, perhaps you can try some clinicl vignette books, not sure which, but there are quite a few in the market, browse through them see which one suits your studying style..either text heavy or diagrams aplenty.
Oh yeah..from my experience about biochem..it's not something you can understand like physio..it's like pharmacology..you have to memorise stuff, and sometimes, lots of it..name of enzymes are pretty easy because they are related to the reactions caused, so, for example if you know that the process involves a phosphate,the enzyme MIGHT be a X phosphatase
Since it sounds like you are cramming, write out on a piece of paper what you will be tested on, but if you are saying everything..i'm not sure how you can cram, but if it's the former, write out those topics, and map out the chapters and notes that you need to study
Good luck