It depends on the routine of these actions. Would need to know more as well, such as bathroom uses, water consumption, appetite, age, and normal behavioral changes. Used to play alot and suddenly stops. Sleeping or resting changes could be a sign of unrest or anxiety. Has anything significant changed in your day to day life that may have thrown things off? I've ran into a few people who changed work schedules and it completely messed with their furry family memebrs cycle. Small changes that may seem mundane to you and me, but could have vast implications to your pet.
ADDED NOTE: a change in diet and lethargy are your immediate signs of concern. Sleeping patterns or styles are usually a psychological change to your pet, and not so much a physical change.