I don't think there's any need to feel anxious. The SENCO (Special educational needs coordinator) is usually a teacher with extra responsibilities in this are. If you are anxious call the school an ask to speak to them. They'll be able to tell you about any processes or plans.
How are things now? My did has been referred to senco she is nearly 4. We've been seen by the inclusion teacher and they've made several referrals. It seems the potty training isn't an issue but more a symptom of a learning difficulty.