It will be fine, especially if leaving by air, because, although the US does not have exit border control, the airline will pass on your info to the CBP.
The date written on the passport stamp is the day on which you have to leave at the latest. So if it says 9 November, your flight must leave at 23:59 on 9 November at the latest
Nevertheless, I always advise people to check this Website once you're home. It should list one arrival and one departure. If the departure does not appear within a week, the airline may have done something wrong, in which case, to avoid being wrongfully classified as an overstayer, you should send a copy of the passport, visa and US entry stamp, together with as much evidence of your departure as possible (such as original boarding passes, passport stamps, card transactions from outside the US) to:
Coleman Data Solutions
3043 Sanitarium Road, Suite 2
Akron, OH 44312
Attn: NIDPS (I-94)
But like I said, you will not be overstaying with your schedule