We've had a number of different things going on here. DS2's teacher brought in the SENco, who advised us to go through GP for a referral to the paediatrician. The GP refused to refer him to the paediatrician, stating that it was a mental health issue not a medical issue
(possible dyspraxia and ASD) and referred him (after giving us a snotty lecture about the NHS budget and school budget blah blah) to CAMHS.
The SENco was annoyed, as she wanted him to be seen by the paediatrician, so she has arranged for DS2 to be seen by:
- school nurse, who has referred him to the paediatrician (waiting for appointment now)
- language and communication team (appointment this week)
- Ed psych (not sure specifically what date yet)
as well as starting him working with a small group that focuses on skills for children with dyspraxia, and a 1-on-1 10 hours a week in classroom plus during his lunch and playtime. His CAMHS appointment is next week.
I admit it seems a bit overwhelming all this at once, but when I have seen those that have had to fight for appointments, I'm certainly not going to complain. I do get worried as there's always conflicting advice though - SENco says paed is the way to go, GP insists CAMHS. Although SENco has no objection with him seeing CAMHS, she says he MUST see paediatrician as well. 
SENco told us that the end goal is statement for DS2, and diagnosis is an important part of it.
Not sure if that helps you at all, but this is what we were told is needed. Have you spoken to the SENco at all? Ours has been really open with information and given us copies of all paperwork (including referrals and IEP), as well as keeping in contact with us by email and in person at the school. Basically she has told us her job is to help us by coordinating assistance for DS2 as well as fighting in our corner for whatever he needs and providing us with the info we need.
Can you arrange to meet with the SENco at your school to find out what's going on on their end and what they need you to do on yours?