Heheheh.....
I have ADHD and will often forget what I was going to. This is mostly because I will get distracted by some means (outside distraction, or just drifting off in my head) and then I move on autopilot to the destination of wherever it was I was going..... arrive in the room and have no idea why I'm in there, and don't always remember. Your example of forgetting as soon as you get to the computer sounds like me as well.
Can't wait to see how I am in old age.
I think that's pretty normal, or not like clinically concerning forgetfulness if that's what you're asking lol.