AITA for telling my wife I needed a mental health day?

Took a sick day yesterday without telling her I was taking it for my mental health - I just said I wasn't feeling well. Spent the day alone, went for a long drive, sat in a coffee shop, and honestly felt like a human again. When she found out later she was mad that I didn't "tell her the truth" and said I should have communicated instead of lying. But also if I'd told her I needed mental health time she would have had a million questions and offered to "help" which isn't what I needed. Am I wrong for framing it as physical sickness when really I just needed to not be around anyone?