Worried for Oggi (133 of 365)

My dog's lethargy is worrying me.
I don't know what happened to him. He doesn't like to move. He just wants to stay in my room.
Do I need to send him to the vet? Is his CBC going to be okay?
Would this mean I will incur another expense? 

Please get well soon, Oggi :(

Please help me Lord :'(