Does a prayer become invalid if someone makes a movement—such as bending a finger or biting a lip—to remember something external to the prayer?

Prayer is not invalidated by bending a finger or similar actions, as this is a minor movement. However, a continuous series of many movements, as commonly understood, invalidates it, unless there is a necessity. Biting one's lips to remember something after prayer does not invalidate it, as long as one performs its pillars and obligations correctly. However, it might prevent one from performing the prescribed post-prayer supplications properly, which could lead to its invalidation if any of the obligatory supplications are omitted.