Nervous is a synonym of Anxious. Anxious is derived from Anxiety. Person does not want (to) Anxiety. Person wants (to) Be. 
Bed is the opposite of Awake. Awake is related to Arise. 
Nervous <--Synonym--> Anxious --DerivedFrom--> Anxiety <--NotDesires-- Person --Desires--> Be 
Bed <--Antonym--> Awake <--RelatedTo--> Arise 