Just check and see how much the batteries have gone down tomorrow before discharging them any more. If they are not holding the charge, then you have problems. Have you checked the electrolyte? What about checking them with a battery hydrometer. That will tell you real fast if they are bad!!!
My coach stays plugged in all the time. If it isn't plugged in, there are parasitic devices that draw power all the time. In the cold temperatures (17 last night) they would become discharged very quickly. The coach has a 4 stage microprocessor-controller charger that knows more about keeping the batteries up than I do