What's the Name of That Book???

Its a YA vampire book with the protagonists name being Marcus (not entirely sure though), he becomes a vampire in the book, there are witches, the protagonist is a teen or maybe 12 years old, the book isn't too long and I'm not sure if it had a series i read it about 8 years ago. The book features this unique writing style where the author separates sections with time stamps (very frequently), like this:

10:30a.m.
And then Marcus went to class very nervous about his newly discovered life.
12:00p.m. ...more