I had approximately no knowledge of embedded systems beforehand. I did well in math in high school and I played around with an Apple II and BASIC as a kid. (Initially, I was just aiming at "engineering" as a broad field; it wasn't until I got further into it that I focused on embedded stuff. My degree was in mechanical engineering, but I took mostly EE classes.)

I switched because I discovered that I love designing and building things. I still love teaching, and I wouldn't be surprised if I did it again.

Why didn't I study engineering the first time? That's a damn good question. The English degree did give me the ability to write reasonably well, but other than that, it was crap.

Mostly, it was just bad luck that I didn't end up in a technical field initially. I went to a liberal arts college and took soul-crushing, thinking-free chemistry and biology classes as a freshman-- that pretty much killed science for me. It should have been obvious, but even as late as my junior year in college, I didn't know that the field of electrical engineering existed. It's kind of a sad story, looking back on it, but at least it ended well.

I can answer that last question... there were not many girls in engineering. There were a few (and they were cute and I worked with some getting their Masters) but the Arts and soft sciences were loaded with girls. That's why I got a BA rather than a BS. I still learned how to code, sat on engineering committees, participated in defenses, did Military funded research on embedded devices, etc., but I had fun with the opposite sex too. You need some balance in life.