Indexing poems

I've been creating a contents list called TOC or Table of Contents for short.
The contents list is in page number order. So I have the contents listed at the start with the titles of poems in page number order.

I would expect the index at the end to be alphabetical.
But the index created in word is also in page number order.
The index of first lines at the end has been created with page number order.

I have had to compile my own alphabetical list of first lines, adding the page numbers.
Of course I could have copied it and done A-Z autosort. Why didn't I think of that before?
I'll do that next time.