Numbness is caused by injury to a nerve. Usually, this is a temporary problem, just like when you sit on your foot and it goes to sleep. Contrary to what every one's mothers tell us, it is not due to cutting off the circulation.
Numbness or a body part falling asleep is due to compression of a nerve or nerves. Once the compression is released, the nerve can start to wake up again. The medical term for this is neuropraxia.
So, somehow you have pressed on the toe or foot, putting just enough pressure on the nerves to the little toe to put them to sleep. This could have been from such things as: shoes that were too tight, laying on the foot for a prolonged period, or walking for a long distance that you are not used to, for example.
If you do not notice any change in the sensation to the little toe in the next several days, then you may want to have your physician take a look at it. You should notice the pins and needles sensation first, as the nerves start to wake up.
In the mean time, make sure that your shoes are not too tight and that you don't rest on that side of the foot. While the toe is numb, it is more susceptible to injury. So, be sure to check it each night for any cuts or sores that you may not have noticed.