The same problem has my girlfriend and I start to experience it with age aswell. If you're going with huge steps towards 30 you're sick of sitting in school. Tho I am still into reading lnegthy text about all sorts of things that interest me and I guess that wont ever change.
My girlfriend got diagnosed ADD too, what isnt easy to get diagnosed with in Germany. Meaning it's not a common diagnosis because most doctors dont know about it or think its bullshit, I dont know. She tho made a test with her counsellor and got diagnosed heavy ADD. She always listens to music on earphones, when she goes out, cause she says that she experiences all phenomena around her simoultaneously and cant filter em properly.
According to this, I have been thinking too if she may be a S. She never got much into mbti, cause she doesnt believe in it, but the one time I after heavy trieing
made her take the test, she got infp. And according to all sfp type descriptions, I havent seen one that fits her at least 30 %.
So its hard to tell what her type would be.