I was about 34. Always struggled in school socially, which then went on into college and university, and any job that involved 'neurotypical' (!) people. I moved to Australia in 2009. There was always some distraction or stressful situation to deal with (finding a job, having kids, buying our first house, renovating, etc) to blame things on.
Once things had settled down, I began to notice these cycles that lasted a few days: a short period of usual behaviour and mood, followed by a few days of shut down, when all I wanted to do was sleep. I went to the doctor, thinking it was depression. He referred me to a psych. After a few sessions and journalling, depression and bipolar was ruled out. He said I had Aspergers, and the cycle was simply a trying to cope leading to burn out pattern.
I work at a bank, which is pretty corporate with an emphasis on social stuff. I was obsessing over my figures (as we can be known to do!) and trying to maintain hitting my targets, etc, but it those that were close to the management and filled a certain role that got promoted, no matter how they performed (ie, I simply couldn't face going to every social function - especially small talking with clients I didn't know, and I didn't enjoy the usual things everyone else liked. Branded the office weirdo!). This made no sense to me. Trying to cope with this and the chaos, mess, (the noise!) and unpredictability of life with young children was leading me to simply turn off for a few days to recharge, where I just wanted to stay in bed, in the dark.
My diagnosis was complicated further as it isn't official! The psych said he would have to perform the required tests, etc, and that would take forever. He said that by giving me my 'unofficial' diagnosis, he knew I'd research it, incorporate my findings and effectively manage it myself. A formal diagnosis would mean nothing, as it doesn't provide for any further support, counselling, etc. My son is 8 and the school psych informally diagnosed him and gave us the same reasoning. An official diagnosis changes nothing. By simply knowing he has AS, we can make changes to cater better for him ourselves.
My youngest is 4 and was formally diagnosed with level 2 autism after a barrage of tests and observations. This is completely different due to the amount of funding and support involved. He gets a teaching assistant, a psych, sensory equipment, etc, through the NDIS.
As for me, changes were made in light of my AS. In particular, I DID go away and research! I'm now a 4th year at uni in clinical psychology, hoping to work with children and adolescents on the spectrum. Better than the popularity contest of the corporate world any day! ;-)