From Wikipedia:
The spoon theory is a model used by some disabled people and people with chronic illness to describe their everyday living experience when their disability or illness results in a reduced amount of energy available for productive tasks. Spoons are an intangible unit of measurement used to track how much energy a person has throughout a given day. Each activity "costs" a certain number of spoons, which might not be recharged until the next day. A person who runs out of spoons loses the ability to do anything other than rest. One of the tenets of the spoon theory is that disabled or ill people must plan their activities to ensure that every day is manageable, while healthy people have a "never-ending supply of spoons" and thus never need to worry about running out. Because healthy people do not feel the impact of spending spoons, they may not realize that chronically ill or disabled people's considerations include mundane tasks such as bathing and getting dressed. Spoons are widely discussed within the autoimmune, disabled and other communities,but the concept of spoons is otherwise considered a neologism.