I faced this same problem last year. Marrow medicine being so vast creates this self doubt. And fear of missing out makes us want to finish the whole subject from whatever platform we are using. I started with endocrine from marrow, found it too much to handle and then switched to bhatia and again to prepladder. And guess what, I didnt finish even a single unit of medicine. As someone who cleared neet pg this year, my advice would be to give least priority to medicine. The yield:effort ratio is quite low and trust me you can definitely answer a lot of questions if you're well versed in physio,patho and pharmac( even pediatrics !) So try to finish everything except medicine, then find out something compact like rapid revision or anything,start solving questions blindly. You're gonna do well. Never start with medicine before you've finished the other 18 subjects because by the time you finish it in say 1 month you'll start panicking that other subjects are still remaining ( or maybe its just me) . All the best!