Hmm, at this point multiple things...
Is the APN selected is the one used from your carrier? If yes the settings are correct (just in case)?
Have you network coverage (how is the signal, have you a edge/2G/3G and so on icons, bars)?
What happens when you try to use the browser or whatever (an error message)?
Could you test your SIM card in another phone?
@s-essa, try to add it manually depending of your carrier (maybe call them or take a look on the web for the settings), always in Settings/More/Mobile networks/Access Point Names and click on the little cross surrounded and don't forget to save.
when i try to use the browser it just doesnt load and said that i have no internet connection.
I entered it manually. i got the details off the website for my carrier.. and i did click save.
Does it take time to activate ? So after i enter it and save it and select it... how long until my internet will start working if what i did was correct?