I felt the same way, and in the last few years growing up has done much to shift my brain to the next gear. Once I knew what concentration felt like I was able to recreate that feeling and focus. No medication involved.
Same! I'll take adderall regularly for some time. Then I'll get a decent feel for what it's like to concentrate and am able to do it without it. I don't know what's the scientific justification for what you and I are able to do but I'm glad I'm not the only one :D
