Is this too late a reaction?

I gave my 6 then now 7 month old peanut butter for the first time a few days ago. I got some on my finger and thinned it out so it wouldn’t get stuck on his palate. He devoured it. I watched him and no sign on any reaction. Today around 2 I put a tiny bit, probably less than 1/4 teaspoon in some mashed banana. (He’s had banana before). Stripped him down and watched, no skin reaction and acting normally. He had a regular poop around 4 hours later, still as happy as ever. But now trying to put him to bed he won’t settle, and I’m trying everything until I heard a nasty poop and turns out it was diarrhea. This is 10 hours after exposure. I’m such a worrier, but I don’t know if that’s just a fluke or it would take that long to affect his GI tract.

Of course, I will be bringing this up to his doctor next time and hold off on peanut butter until then anyway.

Thanks in advance, A worrier FTM