I'm not a doctor, but if you do have ADHD, it's worth trying all the available medication -- amphetamines(adderall, dexedrine, desoxyn), methylphenidate in it's various release forms, strattera, or off label medicine -- modafinil, bupropion or even nicotine patches.

You might also have another condition like depression.

I've experimented with several chemicals (probably not legal where I live) and indeed not all provide both focus AND motivation.

Healthy work habits, enjoying the work that you do, having longer term goals and your work actually contributing to your longer term goals, having hobbies outside work and so on and on -- all these things can help.

Also make sure you lead a healthy lifestyle, you sleep properly, you do physical activity, check you vitamin Bs, hormone levels -- thyroid, testosterone.

You can also do a DNA test with 23andme/ancestry and then analyze the raw data with something like Promethease.

Did you feel "zombied-out" -- completely emotionless, staring at a blank wall, like you have your foot on both the acceleration and the break pedal of a car; I felt that way when taking too large of a dosage of certain stimulants.