First, your question: The preliminary hearing before the Didtrict Judge is followed by a "formal arraignemnt" in the court of common pleas. In some counties, the next step is the trial list. In other counties there is a "pre-trial conference".
I agree with my colleagues, don't even think of representing yourself for the reasons stated. You need a lawyer to help you with this. You may want to discuss a possible Section 17 with whatever attorney you choose.