When I click the buttons to check off spell slots on my character sheet, unequip armor, or remove potions after I've used them in game, nothing happens. 

You're probably viewing the shared version of your character sheet, and not the player version. When you look at the sheet, can you see the tabs for 'Description' and 'Notes?' They should be between 'Features & Traits' and 'Extras.' If you can't see those, that's what's going on. To get to the player version, use the megamenu at the top of the page to go to 'Collections: My Characters' and then find the character in question and click 'View.' Now you should be able to edit.

I just leveled my character up, and whatever was going on went away. Thanks for responding anyway!

Quote from pocketmouse >>

You're probably viewing the shared version of your character sheet, and not the player version. When you look at the sheet, can you see the tabs for 'Description' and 'Notes?' They should be between 'Features & Traits' and 'Extras.' If you can't see those, that's what's going on. To get to the player version, use the megamenu at the top of the page to go to 'Collections: My Characters' and then find the character in question and click 'View.' Now you should be able to edit.

 Bingo! I wish I could give more upvotes.