That was the painting I first saw of hers. As a Freshman in college I decided that rather than take the usual "Introduction to Western Art" type general education class that I would fulfill the requirement by taking an actual Art course (Intro to Painting). I didn't really realize at the time that it would be like a theatre arts oriented person taking Freshman Chemistry (one of our "weeding out courses" in the science colleges). We were expected to fill several notebooks with sketches, images, ideas, whatever - there was at least 6 solid hours of work each week outside of class, and there was 6 hours per week of studio time. Between this class and another ill-advised theory of mine, I almost ended up on academic probation in my first year of school.
Anyway, when we got to self-portraits, Kahlo was one of the exemplar artists. My teacher, who was a photorealist, was absolutely rhapsodic about her work - about her ability to symbolize and illustrate her internal world. Strong praise for a surrealist.