I went to the doctor and told him I felt like a set of curtains.

This classic doctor's joke hangs its hat on a clever bit of wordplay. The humor comes from the doctor's perfectly sensible advice, "pull myself together," being taken in two very different ways. On one hand, it's a common idiom meaning to regain composure or control one's emotions, which is exactly what a doctor might tell someone feeling down or discombobulated.

However, because the patient has just compared themselves to a "set of curtains," the punchline also works on a literal level. Curtains, of course, are often "pulled together" to close them or adjust their appearance. This unexpected double meaning creates a delightful moment of absurdity, where the doctor's professional advice inadvertently becomes a literal instruction for a fabric-based predicament, all without missing a beat.