Learn Russian: Неужели на экране мерцает пятно? - Is a spot really flickering on the screen?

While то ли ..., то ли ... expresses uncertainty between two distinct possibilities, неужели expresses strong surprise, disbelief, or doubt about a single possibility. It translates to 'Is it really true that...?' or 'Really?'. Here, the speaker is doubting their own eyes.

Why is the subject 'пятно' placed at the very end of the sentence?

Russian places the most important, new, or emphasized information at the end of a sentence. By putting пятно last, the speaker emphasizes that the surprising thing flickering on the screen is specifically a spot, rather than something expected like a cursor.

Could I use 'мигает' instead of 'мерцает' for a flickering screen?

You could, but the meaning changes slightly. Мигать means to blink or flash clearly on and off, like a turn signal or a text cursor. Мерцать describes a softer, irregular glimmer, shimmer, or faint flickering, like a star or a dying screen backlight.

How do I read this sentence out loud? Where does the pitch rise?

In a yes/no question starting with неужели, the pitch goes up on the word that holds the core of your surprise. If you are surprised by the action, your voice rises on мерцает. If you are surprised by the object itself, it rises sharply on пятно.