What does 2 Kings 4:16 mean?

Elisha told her, 'About this time next year, you’ll be holding a son in your arms.' She said, 'No, my lord, please, man of God, don’t get my hopes up.' 2 Kings 4:16 - Modern Text Bible

(Elisha promises her a son, something she’s probably given up on. She’s so surprised and cautious that she can hardly believe it.)