Fake twitter account?

[Gman V]

Well lets say theres a kid names "bob" at my school. Two weeks ago bob went to the princapal saying that i called him quote, "blackie" on twitter (hes not even black). First and foremost i was not aware i had a twitter, nor would i say anything like that. I got called down to the principals office,lets call him, "Mr.Bob" mr bob showed me the messages and i denied everything because like a stated before i was unaware of having a twitter. And the messages where from june of 2011. So the next day i let my parents go through my email confident they would jot find anything. They did. At this point i was fraking out because i never made a twitter account nor would i want one. So two weeks go by and through those weeks i researched a few things and so did my school. Yesterday i was called to the office and was shown a print out of the wall or whatever twitter has. It had posts to my friends and bands that i like but like i said i denied it because i did not do it. Now my father was called by my administrator into a meeting and is getting the FBI involved. Im very dumbfounded on why he wont just drop something that didnt even happen at school. And now im feeling suicidal and scared. Please help me understand what will happen.