You mean you thought of this last night?
4 seconds sound clip from the Stagecoach (1939) movie soundboard.
You can hear this line at 01:02:17 in the Blu-ray version of the movie.
Quote context
[...]
- Will you go with me, Dallas?
- I can't leave Mrs. Mallory and the baby.
- I'll come to you from Lordsburg, I swear it.
- Well, I oughta have a rifle and some...
- I've got one! Right here. I got it last night, when they were all asleep.
- You mean you thought of this last night?
- Yeah, don't ask anymore questions. Not now.
- There ain't no Apaches behind us.
- We can still go back to Tonto.
- No, I insist we go on to Lordsburg.
[...]