I tinkered around before then, but really only got it when I read K&R. That's probably not the best place to start now though; even in the unix world, C doesn't have the same place in the ecosystem it used to. The Structure and Interpretation of Computer Programs is a good book if you're mathematically inclined. There are lecture videos of the authors teaching a class from it that are well worth watching too. If you're looking for something more practical, start with the python tutorial, find some libraries for the sorts of programs you're interested in. Sign up for an algorithms class, and maybe combinatorics or graph theory if your school offers them, later if you decide you like programming.
MIT doesn't use it anymore. I think it's a fine introduction for a newbie who is comfortable with mathematics, because it tries to be something like an Elements for programming. It's not really an introduction to programming as engineering, but no book is a good introduction to programming as engineering, and certainly no book that doesn't assume some background.