Why are you wary of using something like that?

I use one of them, and it has been a great help for me for studying and for work. I don't take them during "off-time", i.e., weekends and holidays, and I don't feel like I need them for my hobbies, where part of what makes it fun for me is that I can take my time, shift my focus constantly, and define "progress" by my own internal metrics.

They can work, they work wonders for me. There's also no "magic pill" and they have their downsides. For me, the pros vastly outweigh the cons, and I've tried several times to make a happy life without support of medication and it's just not as good. (Even with trying a more alternative lifestyle, not being in an environment where I need to sit and focus all the time, etc.)

But also, every body and mind are different. Consult a specialist. There's many different types of ADHD medication out there now.

They do. If you don't have a diagnose, be careful with it. You want to be able to execute challenging mental tasks without it. You will still be able to do that after trying such medication, but you will always know, there would be a easier way to do it and that can become a mental block.

I would recommend trying something like l-theanine, or other any of the other supplements which have purported effects on focus.