@dgn15905 Welcome to Mayo Clinic Connect, a place to give and get support.
I am unable to directly answer your question. I'm not sure where you live or what your situation. I've not heard of someone referring themselves exactly but I also haven't worked in that capacity at Mayo Clinic. I think it is most common for someone to receive a referral from their provider. Did you send medical records with the referral? Is there a reason your PCP wouldn't give you a referral? If a referral is an obstacle, you could potentially establish with a PCP at Mayo.
Did I answer your question? I will certainly look up and give what information I can. I will be using the Mayo Clinic website that is available to everyone on the internet.