Upset with myself for being so easily confused + rsd trigger

I have a voice coach, I'm doing an exam soonish to prepare to train as a singing teacher myself. She's also quite busy with other stuff - conferences to do with various aspects of her specialty training, and her side business, performances, and so on. So there are a bunch of dates she's not around, and this week and last week were among them. There was a midterm break the week before that.

I really struggle with routines being changed - I'm totally lost unless it is SPELLED OUT for me what exactly is happening and when. I need time to write it down at the end of the current lesson, or I do well with simple lists of dates when there aren't any lessons, or an online calendar I can check... but having to sift through a load of bits and bobs of info to get the one bit I need regarding the dates I need to be aware of, I'm LOST. My brain just won't process it.

My teacher writes newsletters every month, and buried in the many many MANY paragraphs of stuff I don't actually need to know about, is the stuff that I do need to know about. I either can't find it because my eyes are jumping all over the paragraphs of text, or I'm mentally exhausted by the time I've forced my eyes to read through and find it that I don't retain it and instantly forget as soon as I look away from the screen. At the moment, I'm struggling so badly with this that even making A Task of sitting with my emails at my laptop and searching for the email and trying to find the relevant dates and jot them down is still not working.

(I am currently trying to get my ADHD meds adjusted, for what it's worth...)

I turned up at her house last week but there was no answer. I felt a little silly, but didn't overthink it and went away home, thinking I must have mixed up the dates and I'll go back the following week (my lessons are every 2 weeks).

I turned up today and her partner answered saying she's still away, so no lessons on today. I thanked him and apologised for disturbing him, and headed away to my car.

I felt so embarrassed turning up two weeks in a row that weren't my lesson day, knowing that both are on the doorbell camera. It just really got to me this time. I tried so hard to find the important dates several times this week, couldn't find them (maybe they never made it to my inbox after all?!) and thought that the logical expectation with a big exam coming up soon, would be that I would surely have one this week, otherwise I'd be going 4 weeks between lessons with an important exam coming up which doesn't feel right.

Anyway, I stopped a little over halfway home because I guess I'm having a bit of a quiet meltdown over it. I just really feel embarrassed and ashamed and worried that I will have annoyed her by turning up to her house twice in the wrong days - I did show up on the wrong day once last year too.

Idk but I'm feeling really stupid, embarrassed, like a nuisance, and also a bit worried about preparing for my exam, plus scattered with the lack of a sense of routine. And it's all just hitting me right now.

So I've stopped off to go to a silly craft shop and pick up a cute thingy for my dollhouse and maybe treat myself to a coffee or something before I go home. Going back home felt so much worse for some reason.