For me, photos won't show until you complete the post - then they're there.
that's the way it's always been, and i have done this a bunch.
now with that said, i only have a desk top computer, and a basic camera to take pictures with, that i then download to this desk top.
it always takes the pictures that seem to be the correct size needed to post here, and i'm pretty sure they are much smaller than the maximum size allowed, although at times, i need to resize them smaller.
this contraption has a "resizer" program in my pictures place that is real easy to use, and i only need to tell it to make the pictures a certain size, and it does it. poof, done.
i don't have a phone, so i can't even begin to tell anyone how to do that on those new fangled "smarter than me" phones............