"Appointment booking"

I've had an ultrasound, and was advised I should make an appointment with my GP to review. Unfortunately it is not possible to do over the weekend (or even out of hours as far as I can tell). It seems I need to wait until I'm at work (or rather the GP surgery is at work) to take time out of work to try to make a confidential web transaction, to book an appointment, which will no doubt be for weeks hence. What nonsense is this for the customer and the country? People keep asking why UK productivity is so low. This is part of the problem. I'd much rather do this in the privacy of my own home, at the weekend, in my own time. Why isn't this possible?