Why does my post need approval to be visible?

Because we check the first few posts of a new member. That prevents our site from being littered with spam.
After a certain number of approved posts, your posts will be visible immediately.

Also, we require a valid email address to be associated with your account.

Ok got it. So i just need to wait.

Didn't I gave my email when i created my account? I thought you can not make an account without a valid email.

Didn't I give my email when I created my account?

I don't know. When I registered, many years ago, no email address was required.
But if you didn't give one, then all your posts went through the approval process.

If there's no email required then how come i can logged in using my email?

If there's no email required, then how come I can log in using my email?

The requirements may have changed.
I log in with my user name (the name you see on my posts) and a password.
I do not use my email address to log in.

Here are some instructions from our Help section. The highlighting is mine.

How do I register a new account?

In the top right-hand corner, mouse over the "Log-in" link, and you'll see a pop-up window with log-in and registration options. You can register using your Facebook or Google+ account, or you can write your desired user name in the "Choose a user name" field and, i