Does your GP know you will be waiting until March? They may be able to phone up and ensure they can't do anything earlier.
When Phoebe was a baby we were told we'd need to wait 3-4 months for our appointment (regarding a possible neurological condition too - turned out all clear though). I reported back to the GP, she rang the paed's rooms and all of a sudden we had an appointment that week!
For something like this I'd be making sure the GP knows you are waiting so long. It could be that she shouldn't wait that long and the paed may force the booking forward. Good luck with it all. x