No, your diamond is not too small!
I see posts very often on here asking if their ring is too small. With the rise of lab grown and maisonette (which are also nice - no hate at all but I think it’s more common to go for larger stones) I usually always assume the stone is natural if it’s “small”. “Smaller” stones to me look elegant, sophisticated and more akin to quiet luxury. Some of the coolest girls I know have 0.25ish diamonds or even gem stones instead of diamonds and it looks so chic.
Obviously everyone has their own taste and karat preferences but I had to say this given the amount of posts re small diamonds I see in this sub.
Just my opinion!