Thinking how long this illness would last/would be over(phrase/modal usage)

Question

Let's say you were storytelling your childhood illness. And you say:

It's not not my cup of tea to fret, but the constant sneezing, chilling due to fever, and body weakness I was experiencing was unbelievable. I was thinking how long this illness would last/would end.

Which is correct? Both don't sound right to me, because I was thinking if I should use the 'first conditional' modal verb over the 'second conditional' or should I just need a set phrase here(as I've said the bold letter are not good to my ear.

Answer 1

The verb "last" is a good choice since "how long" means "a period of time", whereas "end" presupposes "some finishing point in time". "Would is fine here. You have reported speech with past continuous in the main clause.