Failed my test- Where to go from here?

Hello all

Sadly failed my test this morning which I am absolutely devastated about. Drove really well but failed to stop for a child who was waiting at a pedestrian crossing. I didn’t stop because traffic had blocked the other side of the crossing so they couldn’t cross anyway, which I wont do again. Beyond that Im happy with how it went.

In terms of whats next, what is the quickest way of getting a test? I booked this one through my instructor as they had some for todays date on 29th November, so basically two months away. I really dont want to wait 2 more months, my instructor said he will try to help me but should I just book a DVSA one and use Testi/Driving Test Now? Any help would be great and definitely cheer me up! Thanks