Fonts rendering strangely in Photoshop

I posted this in my personal journal yesterday, and so far haven't been able to fix it, so I thought that I'd try here, as well. Any help would be greatly appreciated, because I'm pulling out my hair, here.

For whatever reason, every time that I go to use a pixel font in Photoshop, regardless of the image that I'm using it on, it becomes unreadable, like I have a very strong antialias on, almost. But I don't. Characters that should have openings - O, for example, or p, are completely solid, as are a and e. The other characters seem like the lines are two pixels wide, but the character remains the same width, if that makes sense. Moreover, when typing, hitting enter does nothing except move the cursor to the beginning of the row, where it promptly allows you to type over what you'd written previously. And by "over", I mean that the characters actually overlay.

I've rebooted, resized to 72px/in and 72.27px/in, I've tried putting fonts that I usually use at 8 points at, say, 7 or 9, or 7.5 or 8.5. I've created entirely new files, I've copied and pasted and opened and closed and closed the program and reset everything to default settings, and done everything that I can think of, and I'm about to cry, y'all. I even uninstalled the whole program earlier today, deleted all the files, and then reinstalled from scratch. It's only pixel fonts that are doing this - Script fonts and regular fonts look just fine at the sizes that I normally use them at.

Anything that y'all can think of that might cause this/fix this, would you please let me know? Has anyone else had this problem? I can't think of anything else to check, but maybe I'm just overlooking something.

(Visual representation of what's going on:
The last line, the weird solid one, is where I tried to hit return and instead of a new line, it just typed over itself.)

[ETA: YAY! There is much squeeing and rejoicing, because kaena figured out the problem. Yay!]