You have been given lots of conflicting advice! This is partly because the training for optometrists and opticians may vary between countries as well as the ease in consulting an ophthalmologist.
In the UK, most doctors (GPs) do not have a slit lamp bio microscope to examine a scratched eye with, yet MOST optometrists will. GPs often send their patients with minor abrasions for us to check with our equipment.
If anti-biotics are required, these can now be bought over the counter at the pharmacy in the UK. Your pharmacist can sell you these, but like a GP, cannot examine the cornea first.
In the UK, under the national health system, in order to see an ophthalmologist, you need to see your GP first, unless it is an ocular emergency (you would be in so much pain you wouldn't be sitting at your computer asking questions).
So, here, the optometrist would be the most accessible, and relevant person for you to see first.