What is going to happen to me if I changed the milligrams on a prescription from 20 milligrams to 25 milligrams?

I have been in and out of programs since 2009, I did very well until I was introduced to amphetamines (adderall) I have been doing things I never would have done before. My mother said she do not even know who I am anymore. I went to the doctor for a prescription and because it was too early to fill it I changed the mg to 25 mg so the insurance would fill it. The pharmacist said she needed to call the doctor to verify, by the way it was not my prescription either it was my sons. I have never been in trouble before in my life, I live in Fulton county New York and I’m not sure what happened at the pharmacy last night after I left. I told the pharmacist to just give me the prescription back because I did not have time to wait and she refused, I knew immediately after giving them the script I was going to end up in trouble because it is just so wrong. I have contacted impatient and they said I do not qualify to be admitted because I'm already on a suboxone program, and amphetamines are not enough reason for insurance to pay for impatient. So I contacted outpatient and I have an appointment for the 15th for an intake. I truly know I have a problem, it feels like the drug possesses me to do whatever I have to, to get it.