The picture below shows a st.selectbox() on the left with the icon positioned nicely to the right and inline with the label.
On the right is the st.metric() widget with the help icon positioned below the label.
The default alignment puts the question mark symbol on the right-hand side of the label. You’re likely seeing the question mark symbol below the label due to the size of the column/this is probably a bug. If you take away the columns or reduce to two columns, does the positioning of the question mark symbol change?