Latest questions about "friends list"

Ex deleted or blocked me on Snapchat, but every couple weeks I get a notification that "EX has added you!". When I open the app and check "Added you" the person isn't there.

So one of my friend's account all the sudden said pending and I got really nervous. I thought they removed me or something.

I added a person on Snapchat. The name comes up on my friends list, but when I click on it, it says "Loading...." underneath it. The person hasn't added me back, but what does the loading mean?

I accidentally blocked someone on Snapchat, and then unblocked them when I realized what happened. Do they need to re-add me as a friend?

On Snapchat there is a list: snapchatters who added me. But I wonder, are that only the friends who added me?

Accidentally I blocked someone who was in my best friend list but 2 seconds later I unlocked him, but still I can't see him in my best friend list.

I deleted and blocked someone on Snapchat, and when I try to re-add them it won't let me because it says I have to unblock them before adding them.