No milk supply at bedtime

I’m EBF. Not always, but several times this week, bedtime rolls around and when I go to feed the baby I have no milk. My breasts feel totally empty. She nurses for five minutes then cries and whimpers. After she calms down, she goes another 25 minutes, but I worry she’s not getting enough milk.

Why is this happening? Should I supplement?

On background, she feeds a lot at night (usually an hour after going to sleep, then again at 10pm, 1, 3 and 5am), which I continue to do because she wakes up legitimately hungry. I never have nighttime supply problems. Also, we have started solids, but this happened before then too.

Any advice would be most appreciated!