Dark Harbor - what about the watches?

हे folks, I've just re-watched Dark Harbor yesterday night and there's this scene shortly before the climax, when Alexis checks the time on David's watch. David seems kind of pissed of या even alarmed that she isn't wearing her own watch because she usually always wears it. Did आप understand why she isn't wearing it या why this seemed to be a problem for David?
And shortly afterwards the unnamed young man says he likes David's watch. There has to be a special meaning behind this statement, hasn't it? Can आप help me there?