I have started having a numbing sensation in my toes. This happens when wearing shoes. What could this be?

Tarsal tunnel. In addition to morton's neuroma, tarsal tunnel syndrome can also produce numbness in the foot and toes especially when there is a flattened arch profile. Poorly fitting shoe gear can exacerbate this condition. Hey good history and physical examination and often diagnostic studies including x-rays can help to determine the cause of your numbness. Contact your podiatrist for an appointment.
Tight shoes. Does it happen when you aren't in shoes at all?
Numbness. Most likely its called a morton's neuroma. This is a pinched nerve between the knuckles of the foot just behind the toes that are involved. Usually the 3rd and 4th. Avoid tight constricting shoes with heels. Advil, alleve, Ibuprofen can help reduce the swelling in the nerve. Sometimes a steroid shot is needed if symptoms worsen.