How do you pay for additional tests if you fail?
You can for additional tests either online or by phone.
I see what you mean. I have another concern. With my request, I included my phone number. Is it possible that I'll be contacted in that manner?
Yes. The FOIL office surely will use that phone number to contact and notify you when your records are ready for you to be inspected. If you didn't submit a phone, then you'll be notified by mail.