How to tell if my toe is dislocated?

Look at the toe: If the toe looks different in how it lies or going in a different location, a [displaced] fracture or dislocation may be present. If the dislocation is at the base of the toe, it might be more subtle looking at it. Limited motion, pain and its appearance on x-ray make this diagnosis. See a podiatrist.

Suspicion would : Come after an injury and an x-ray would confirm.

Location, location: Expect pain, an angular deformity at the joint and distorted or impossible toe movement in it's normal range.