UPDATE: I think I figured this one out. The template that I've been using for this project was huge and I didn't notice that it was twice the size that it needed to be. This caused the placed files to be too small (half the size of the template) so I think InD was confused with what to do with them so it only created a tiny thumbnail. I think the template that I downloaded must have been created at 600 PPI. Not sure. Anyhow, leaving this here in case it helps anyone else.
I'm having an issue that recently cropped up. When I'm in InDesign with my document open and I go to File/Place, select my image/InDD File/whatever other file, and I click once, it is only inserting a tiny thumbnail. It is forcing me to drag a box every time, which is annoying. This wasn't doing this last week, but I don't think I've changed any settings. Normally one click after choosing place and then choosing my file inserts it at the size of the file.
I've updated InD. I've restarted my computer. Is this a setting somewhere? Google isn't helping me on this one.
The template was a PNG, which I can't open directly with InDesign, so I just created the InDesign file at the same resolution as the template, not thinking about the pixel->inch numbers. The other file I was trying to place on top of the PNG was in inches. Anyhow, it was partly a weird glitch in InDesin, and partly my rush to get the job done, and partly my newness to InDesign which I don't use nearly as much as Photoshop.