Yes, this is one of my biggest difficulties. I almost had to quit my college course, because I simply couldn't organise myself - but then got a diagnosis and got support, so I now have a support worker who is brilliant.
For me, the difficulty is as follows. I can make up a detailed plan for how to organise my life, but it's the actual execution of the plan that is hard - the switch from planning it to doing it. I find it hard to switch from one thing to another, and I get overwhelmed by assignments that seem vast, because I have no idea where to start, or how long things will take. A big difficulty is that my mind can only focus on one thing at a time, and once I'm focused on something, it's as if everything else doesn't exist. And at college we are given several assignments simultaneously, which throws my mind into confusion. And of course, as well as college, there are the numerous other things I have to organise in my life - keeping my home tidy, making sure I eat healthily and regularly, making sure I go to bed at a reasonable time, making sure I exercise regularly, making sure I relax, etc. I find it impossible to juggle all these successfully. What happens is that I either end up focusing on one to the exclusion of all others, or I end up with a confused sort of freeze, where my brain is overloaded and shuts down and does nothing (well, escapes to the internet!).
_________________
'If the shoe doesn't fit, must we change the foot?' Gloria Steinem