Why does my website look funny with Let's Encrypt?

I activated Let’s Encrypt the other day after reading about it in the monthly newsletter. Now, when I view my website (http://carolynapappas.com) using https (https://carolynapappas.com), nothing is formatted the same way. Everything is aligned left and even images are not visible. Is this supposed to be like this, or is my Wordpress theme not compatible or something like that? Please forgive my ignorance. I’m really not very educated on these things.

Edited to add: I went on the site Why No Padlock? and I figured out my child theme stylesheet had an insecure link in it and I fixed it. All of the images links look like they are still unencrypted. Do I have to go into each post and change it? That seems unreasonable.

I ended up adding an “s” to the http in my site address in Wordpress and now everything seems to work.

I documented this here if anyone else is having similar difficulties: