You're sounding quite upbeat and happy in your posts which suggests that you are quickly mending as PCS almost always makes you low and anxious. I did the same as you, came off the back of my BMX and wacked my head on the floor. I was confused and disorientated for about 20 minutes after and I don't remember much of it then I started to develop PCS a few days later. Again the docs told me I was fine as I checked out fine in their scans and neurological assesments but even now 7 months on I'm basically a different guy to who I was before my accident. I had the gushing sound in one ear (which I still get when tired), was sensitive to light and sound and suffered severe deperonalisation, derealisation, depression and anxiety. It was hell. Fortunately you seem to be ok but yes, get your neck checked out as I've heard lots of stories of people who think they have PCS when actually their neck is just out of line. All the best.