PhD Historian pointed out to me that some of the comments he had submitted hadn't been showing up and so I went in and found a lot of comments awaiting approval that I hadn't received the email notification for. (I have it set for Blogger to send me an email when a comment is submitted and then again when I approve it so I know it went through.) I'm not sure what happened, but I've set it up again with another of my email addresses and I'll keep an eye out on the Blogger dashboard as well.
Sorry to everyone who submitted a comment in the last few weeks and are just now seeing it show up! I'm hoping I didn't miss any legit comments in the sea of spam comments, so if something you submitted in the last month didn't post, try it again.
Thanks for your understanding!