As much as I dislike diagnosing strangers on the internet... this is classic ADHD. The brain doesn't really form working memory so short-term things just don't exist unless you see them. Meds help but even still I rely on a lot of those same tools you described. I can't live without my calendar with everything written down. I have daily alarms for set things in my schedule so I don't forget. Notes around my workspace that don't go until the task is 100% resolved. I've also learned to organize my house so that as many things as possible are visible. If it's away in a cabinet then it may as well not be there so I have a ton of nice-looking baskets and things all around for organization. I think the only things in my house that are really tucked away are dishes and cleaning supplies, mostly out of necessity for space/safety. And even those I'll remember because they a separate task will drive me to need them and seek them out.
I spent years thinking I had a serious memory problem. A partner once said my memory was worse than her ex who had brain damage. I accepted it as just a part of me. Turns out, I have severe ADHD and the Adderall does wonders for my day-to-day functioning.
Some doctors can be real shitty like that sometimes. The medical community's understanding of ADHD has really evolved a lot over the past couple decades, but a lot of people are still stuck in the mindset that it's mostly in kids or that if you're managing your life then it's not worth worrying about. The good news is you can bypass them! Typically a good doctor will send you to a therapist for an eval, so you can just find your own to do the test. It usually takes longer to get an appointment, but if you can get with a psychiatrist and not a psychologist you don't even need to go back to a doc for meds. Psychology today's website is a pretty good starting point to find someone in your area that focuses on ADHA, and possibly even adults with ADHD. The diagnosis takes some time and often finding the right meds can be a long journey sometimes, but when you find what works it can be life changing.