。
Something's wrong with my watch.
Literal
I [of-の] watch [topic-は] somewhere condition [subject-が] bad.
The idiom 具合が悪い ('to be in bad shape, to be unwell') is used for watches, bodies, machines alike. どこか ('somewhere') introduces an indefinite location — 'something's wrong [somewhere].' This indefinite+vague formulation is very natural for 'I don't know exactly what, but it's off.'