Incorrect truncation of a series expansion


What is wrong here?

fExp = f0 + f1 Sqrt(s) + f2 s + O(s)^(3/2);
{s fExp + O(s)^(3/2),s f + O(s)^(3/2)/.f->fExp}

Returns

{SeriesData(s, 0, {f0}, 2, 3, 2), SeriesData(s, 0, {}, 3, 3, 2)}

or f0 s+O(s^(3/2)) and O(s^(3/2))} in a traditional form.
The latter result is incorrect.