My personal belief is that sabotage on a large scale throughout the United States is highly unlikely. While large sections of individual states could be affected, with our communications systems, roads and people who are willing to drop everything and help, it is highly unlikely that aid would not be quickly forthcoming.
Some sort of personal toilet facilities with lots of water and basic stored food should last you even in an apartment setting.
For your son, check the facility he is in to see if they maintain backup supplies for short term interruptions. If they do not, arrange for the possibility of bringing him back to your apartment as bringing emergency supplies to him could result in you being forced to share whatever small provisions you have with others on site. Do not feel bad about not being able to share limited supplies to take care of yourself and your son.
Finally; and most importantly, keep your mouth shut about your preparedness, or you may find your supplies gone by the time you come back from picking up your son.
Good luck!
Bountyhunter