i'm assuming you mean by a licensed doctor/psychiatrist/etc. if so, i think you could bring it up to them directly and ask straight-forward: "hey, i'm thinking i am experiencing xyz condition. could you walk me through what is the process to get properly diagnosed?" i'm sure they'd be more than willing to point you in the right direction or refer you to a specialist who would know better

I basically explained what my symptoms were like I get meltdowns (crying spells) and I can have a temper. I got put on Zoloft when I took a test. I tested positive for Depression and anxiety just a few months ago. I understand what it's like to be scared and nervous. Welcome to message me if you want more details or have questions.

Depends if it's psych. Contact a mental health clinic and ask for an evaluation. Or if they are accepting new clients. If it's physical just talk to your primary care provider and tell them the symptoms you have. Generally, if you did Internet self-diagnosis they will flat ignore you or mislabel you as a hypochondriac. So I've always kept myself diagnosed to me and just asked for an examination and told them my symptoms.