Well don't feel so bad. My daughter is 15 and I am still going through it.
I manage our company from home, manage all travel, President of the cheer boosters, keep track of when I am mom taxi to violin lessons, cheer practice, private cheer trainer, etc.
I make a list and follow my list. I may not get everything done in order but I have my guideline. I also use reminders on my IPhone. It is critical that I do not forget certain things such as Accounts Payable and Accounts Receivable!! I am good with the numbers and managing that aspect of our business, I think I focus on the company's daily functions and then I lapse on everyday, mom things. I have all confirmation #'s and such for hubby's travel with me because he is known for calling me and needing a number. When I make reservations I put it all in my phone. When I have appts and such, it si on my calendar in the phone and I use the "alert" function to remind me of something.
The Alert function on the IPhone when you add something to the calendar has been great for me along with my lists.
Good luck