As a current student I have a bunch of things that come to mind about school but not too many about the profession itself. The biggest shock for me was the scope of an architects responsibilities. When I started, I had no clue what an architect actually did. I just assumed it was drawing plans all day. I had no idea what building sections, wall sections, elevations, stair details, etc. etc. etc. were.
First, you learn model building techniques, basic drawing conventions, and the types of drawings. Then one day you wake up, drafting is a breeze, and you begin to learn about materials, construction, structures, and building systems. I still learn something new about what architects do at least once a week and I've been in school for a few years now. Each year is more difficult than the last because the projects are larger buildings with more complicated programs and a broader scope (when I started, I never thought I would be doing mechanical diagrams for the hospital I designed), but at the same time, each year is easier because you're more comfortable and confident as a designer.
Another misconception I had was this romanticized vision of getting struck by inspiration and sketching beautiful buildings and making people cry and whatever. This isn't the case. Architecture is more about the intense cycle of critique and revision and less about living on the whim of a muse. Sure, there are moments where you finally get hit with what you've been searching for but these usually come out of the cycle.
Speaking of the cycle, get ready for it. It can get boring and just plain grueling staring at the same projects for weeks on end struggling over the same issues. But it's not all bad. I wouldn't do it if I didn't find it enjoyable most of the time.
As far as working, the first few years are generally tough regardless of where you work. The places I've interned at weren't horrible but they weren't as interesting as school. Lots of time staring at Revit and AutoCAD doing seemingly endless construction details and a lot of time on the phone trying to get ahold of a manufacturer to get an assembly from them so you can put it in the drawing. The great thing about most firms I've visited or spoken to people about is that architects are pretty laid back people and the offices have that atmosphere. There are strict deadlines and at times long hours, but it's not Wall Street.