Well what I do is I set my alarm on my phone and then strap it to my ankle, then after about an hour the alarm goes off waking up my foot!
Well the first thing I would be thinking of is your shoes, either they are improperly fitting and thus cutting off the flow of circulation, OR, you are tying or strapping your shows too tight and cutting off circulation. I would start with the cheapest thing which is the cinching down you shoes too tight, especially the strap nearest to your toes, but start off by keeping them all sort of loose from what you have been doing.
If that doesn't solve the issue try a thinner pair of socks while keeping the straps loose.
Next, can you feel the cleat plate under the soles of your feet when wearing the shoes? if so you may want to get a better footbed...regardless you might need to go to a bike shop that sells Specialized stuff, they have a foot thing you stand on and it takes a reading of your foot, based on that reading they get you the proper Specialized footbed for your shoes.
Next thing to try is to go to a bike store with your shoes and see if they think they're too tight, they could be too tight on the tops the shoes by your toes meaning you'll need a wider toe box shoe; and or the shoe is too narrow.
I think it has something to do with your shoes as l outlined above, there are other possibilities which I don't think is the case, stuff like pressure on some nerve in your back, so if the shoe thing doesn't work you could try seeing a chiropractor which might be cheaper than a pro bike fit which is my next suggestion.
Ok, next suggestion as I promised, get a pro bike fit because your posture could be bad, BUT be sure to tell the fitter you specific problems...and any other problems you experience while riding.
The only other suggestion is going to a orthopedic place and have some orthotics made for your feet, problem with those is you will need new shoes because those are relatively thick.
Have you checked to see if your feet are swelling when riding? If so doctor time.
You can't ignore this problem either, because you could eventually do lasting nerve damage so you need to get it taken care of, and if none of that stuff works it may be time to see a sports doctor.