Just want to reiterate the importance of sending in the documentation as early as possible. If my memory serves me right, it took more than six weeks for me to receive a decision regarding accommodations. Granted, ETS was updating their website at the time which caused a lot of distress, but I still think it's prudent to submit everything well in advance of the test date. In addition, I'd suggest remaining cautiously optimistic regarding the approval of the requested accommodations. I thought my condition was severe enough to justify a double time accommodation, but apparently ETS thought otherwise (I only received 1.5 time). That said, it's good preparation to take a practice test or two with the standard time allotment--at least until you've secured the additional time.
Good luck!