Sounds like nerve. Most likely condition would be a pinched nerve. The nerves that supply the feet stem from nerve branches traveling from the leg. The "pinch" could be from the back at its root, but it an also be locally due to musculature. Another thing to be checked is circulation because if blood flow is hampered to a an area, it can cause pain and reduce function in the nerves. Get checked properly.
Sounds like a nerve . Compression or entrapment. However, it may be stemming from your back as opposed to in your foot. I would see a neurologist for emg-ncv studies.
Nerve. Actually, there can be a problem with the back (potential herniated disk) that can pinch a nerve and affect the big toe. I know because i had what is called foot drop, which was brought on by a herniated disk in my back- l3-l4. Hopefully not your problem, but consider and get checked. Duration is important!