Question

ag·o·nize
 ( also Brit   ag·o·nise) /ˈægəˌnaız/  verb  , -niz·es, -nized, -niz·ing [  no obj  ]
  : to think or worry very much about something
  — usually + about or over
   She agonized about what she was doing.
   The coach agonizes for days over the choices he has to make.
   The architect agonized over every detail of the planning.