Brain damage

One of the things that I have to go through everyday is the struggle to focus. I have the shortest attention span. Combined with my poor memory, I really find it hard to survive medical school. Sometimes when I do focus, and it feels like I am understanding whatever I'm reading, that info will disappear with haste. And sometimes, when I try to put some more effort in memorizing, my head will hurt. Not the taking it part, but the part when I need to try and retrieve the already 'stored' information. Happened a few times, so much so I think I sometimes purposely try to avoid doing it. Even when I actually do want to try, my body or heart will automatically push it away. The same with studying in the first place. The moment I sit and look at some notes or book - it feels like something is reeaallly wrong and pushing me away from it. Weird.