No, simply because "Et tu, Brute?" was not what Julius Caesar reportedly said according to to ancient sources. This phrase was popularised by William Shakespeare. They wouldn't necessarily have meant anything to anyone before then.

Several ancient sources have Julius Caesar saying exactly nothing upon being betrayed by Brutus. Plutarch's Life of Caesar (Loeb translation) says only this of the event: "when he saw that Brutus had drawn his dagger, he pulled his toga down over his head and sank"

Shakespeare probably got his inspiration from Suetonius. In his Life of Julius Caesar, he mentions that according to some sources the last words of Julius Caesar "καὶ σὺ, τέκνον" ("And you, child"). From the Loeb translation: «And in this wise he was stabbed with three and twenty wounds, uttering not a word, but merely a groan at the first stroke, though some have written that when Marcus Brutus rushed at him, he said in Greek, "You too, my child?"»