Hey Mind_Games and welcome to Bluelight! I see that you're relatively new, so I really would encourage you to acquaint yourself with some of our forum guidelines. Also, just perusing the forums and researching content that you're curious about will give you a better idea of how to construct an effective thread. One thing to understand, is that we don't close threads for personal reasons. There are guidelines that we use to try to keep the forums as on-track as possible.
The primary issue with your thread is that it is pretty vague and is really not something that anyone can answer with certainty. In fact, there's no way to actually tell that one person definitively has ADHD and another does not. The best anyone can do is guess.
The problem with stimulants though, is that, practically every human being who has ever taken them remarks "Wow, I'm so much more focused; I have ambition; all this material is so interesting!". It's really the characteristic effect of stimulants. They make you feel good and give you motivation in various forms.
You have a few options. You can pursue using stimulants illicitly, as needed whenever you are having trouble focusing on your studies or you can actually consult a psychiatrist about how you feel. I would really recommend the latter. There's no need for you to get into drugs. Stimulants are effective for some folks and not for others. Some get benefit temporarily and some (are rumored to) experience permanent benefit.
If you ever have questions regarding safety we're here for you, but we definitely can't diagnose.