Can someone explain acouple thing to me about Twitter?

[I love my PRINCESS ♥]

I responded to a celelbrities tweet..
she isn't following me... would she still get it?

and if she responded, where would I see it?

or do they need to be following you aswell?

Even one of my friends who also follows me
commented on one of my tweets
and it only showed up on their page...
is that how its supposed to be?

also... how does it work when people do #thiskindofthing ?

It's soo confusing!

[SuPaNOvA_AcT107]

If you've responded to someone on twitter then yes they will get your reply in their reply box, but it just depends whether they will read it or not. Since it's a celebrity, this person will probably be getting lots of replies from other twitter users to her tweets, so it may take her a while to read them all. But hopefully she'll get to yours.
If she happened to respond to you then her reply will show up in your reply box as well as on her twitter page. To look at your reply box to check your replies - on your homepage of your twitter there should be, under the 'home' heading on the right column, your twitter name with a @ sign in front of it. So it should be - @( your username). Click on this and it will show you if you have any replies to your tweets or if anyone has mentioned you in their tweets.
You should probably see your friends reply in this as well.

The answer to your last question is that on twitter people make up or start up topics that they want to talk about. When they put the # sign in front of phrases, words or sentences, it's just indicating that it's part of something that they want to share with others about that particular subject. Usually when the # sign is in front of something it goes blue and it can be then clicked on and it will show up on twitter other people talking about the same topic. Also, when you're on twitter, you'll see on the right column on your home page a small heading called 'Trending Topics' which is topics that people are talking about that are very popular.

Anyway I hope this helps, and I know it's very confusing at first but after a while you get used to it Good luck!