Failed .. again

Im just venting a little here. Im 19 (f) - I have been diagnosed for a few years now, but i’ve only recently been medicated and really been trying to learn how to “manage” my ADHD rather than just… push through it. Which has never worked, of course. I just left my classroom confident Ive failed my test. I pulled all nighter and hardly got any work done anyway… Im trying not to beat myself up too badly, I know the self loathing spiral will only make things worse. But Im still just so disappointed in myself. Im embarrassed to be the only “failure” among my siblings, and that I keep making the same mistakes over again. It’s comforting to see that my symptoms are “real” by reading others posts on here, so I can know im not just lazy or broken or just plain stupid.