I've been self-diagnosing.
In general, this is probably a bad practice. Firstly because I am not a licensed medical professional at all, and secondly because any website ready and willing to tell you what's wrong with you likes to say things like, "Tuberculosis," and "Cancer." My two favorites.
That being said, there are times were I have found self-diagnosing really helpful. My friend Alex once had a swollen finger from biting at his cuticles; after a few minutes of searching online, I was able to tell him what was wrong with it and encourage him to go to a doctor for a bacterial infection. Had we not dabbled in self-diagnosing, he probably would've waited longer before going, continued to be in pain, and continued to wave his puffy finger around at unsuspecting bystanders.
For the most part, I find self-diagnosing more of a calming tool than a genuinely useful one. Finding DSPD is in that vein - when I was a baby, my parents called me the Vampire Baby because, according to them, I had my days and nights mixed up. In terms of my own experience, I can't remember many nights past elementary school that didn't involve me going to bed, staring at the ceiling for hours trying to fall asleep, and waking up feeling like death. In high school I just stayed awake, usually to do homework, but it meant that for at least one semester of school I got about 2 hours of sleep a night. Not fun. Not nice. In college it was just the same - I seem to be, mentally, about 4 hours behind everyone else. Which fits perfectly with DSPD and makes me think, "Hey, I'm not insane! This is perfect!"
The face of evil
Having (I think) never been to an allergist, I also self-diagnosed allergies. It's not like it's hard - being around cats makes me sneeze and wheeze, touching my bare skin to grass makes me red and itchy, and when I eat heavily citric foods I get really ill. Similarly, citric acid in soap makes me itchy. Based on that, I have to assume that I am allergic and/or sensitive to cats, grass and citric acid. That assumption has heavily reduced my exposure to all three things which, as it simultaneously limits associated adverse reactions, makes my life a whole lot more comfortable.
I've also never been to a sleep centre - and I may never go. That being said, I like to imagine that there is an explanation for my lifelong failure to fall asleep at the same time as everyone else or wake with the same perkiness my mom shows every morning. (Seriously, the woman is incredible. I have never met anyone so cheerful at 5am.)
What do you guys think? Go to the doctor, figure out your own explanation, or mix it up?