When to use an exclamation mark and when not to use an exclamation mark after Oh?

Use an exclamation mark after "Oh" when expressing strong emotions such as surprise, excitement, or frustration, as in "Oh! I can't believe it!" However, avoid using an exclamation mark when "Oh" is followed by a more neutral or reflective statement, such as "Oh, I see what you mean." In these cases, a comma is more appropriate.