Ricky - I'm not sure what you mean by "applied for a repeat prescripton for your dad" - if it was a prescription drug, it should be on your dad's record, not yours, and if you don't require hayfever drugs, your doctor will not be prescribing you drugs you haven't been diagnosed for.
If you don't have hayfever on your medical records, your doctor can confirm this for you, and if you talk to them, they should be willing to write a letter of appeal.
If you DO have hayfever on your medical records, why is it there? If you went in and pretended to have hayfever in order to get hold of a prescription for someone else ... well ... I'm sorry, but no matter what the circumstances, that doesn't really smack of honesty, integrity, or even common sense - you could try coming clean with the doctor, throwing yourself on their mercy, and then getting their help with an appeal, although they might not be very amused!
For help with the hayfever problem, talk to your doctor. For help with alternative careers, talk to your AFCO - they can advise what options are open to you, if you haven't considered alternatives already.