A couple of other things about traveling coach and mobility issues.
Amtrak no longer hands out pillows in coach. You can buy a "passenger comfort kit" in the lounge car but getting there is a problem and the kit is pretty skimpy on comfort. Most coach passengers bring their own pillow as well as a blanket, it can get cold at night but the blanket also can serve as a way to hide valuables.
The other thing ... Redcaps are your friends. Use them as much as possible. The have electric carts to move you and your luggage to and from the train, especially in Chicago. They are free but will expect a tip, it's really worth it. They are generally waiting train-side when you arrive. You will have to seek them out for boarding however, unless you are in the first class lounge. Explain what train you are going out on when you de-board and perhaps you can arrange for the same Redcap to come pick you up at boarding time. Often they will take you to your car before general boarding begins, giving you a better seat selection.