Yes, you can attempt the same mock test as many times as you like. Each attempt is saved separately in your test history, so you can track your progress over time.
Your dashboard shows your best score and average score across all your attempts, along with a score trend chart for your most recent tests.
If you'd rather practice without it counting toward your official test history, try Practice Mode from the Mock Tests section — it lets you drill questions by tier without affecting your attempt records.