It sounds like your feet are definitely giving you some trouble and I recommend seeing an orthopedic specialist in feet or a podiatrist
. Given the timing and the association with wearing tight shoes for several days, it is very likely that your symptoms now are related to the several days you spent at the conference. Typically nerve compression of a large nerve will cause sensory deficits in an area that corresponds to the territory innervated by that nerve; the distribution of the outer edge of the toes does not fit the distribution of one of the larger nerves in the feet. However, it is quite possible that you may have injured some of the smaller nerves in the periphery and that is what is causing your symptoms.
The best way to determine exactly what is going on and if any treatment is needed is for you to see an orthopedic specialist in feet or a podiatrist. It will be important to do a thorough exam of your feet and ankles, especially a neurologic exam looking for any other deficits. Hopefully this will be a self-limiting problem that will go away on its own with any need for significant intervention, but it is worth talking to a podiatrist about ways you can prevent this from happening again, either by changing your footwear or possibly using inserts to help stabilize your feet.