Did I lose my marbles?

So....
There I was...
Floating comfortably in this stream of life called acceptance enjoying a well paid job in pharmacy having no bumps in the road, well and truly enjoying the dollars$$$. Being a female shoes sexy shoes not just any shoes I will point that out.
...Suddenly I decide at 40 to throw all this in the titty bin and study full time medicine. Suddenly my days have become a constant assessment of anatomy and physiology medical terms, Latin words that I previously assumed were on some exotic menu...
My computer has become my lover.
My refrigerator my fuel tank.
Would I make this decision regardless of the shortcomings?
Absolutely. I am doing what I wanted to do a long time before. Why would I choose to stay in one place?