Given the position you are starting from, I think the best thing to read would be an engaging but broad overview of economic thought. That way you can better decide what interests you to read next. And it wouldn't hurt to read a tried-and-true classic.
The Worldly Philosophers by Robert Heilbroner would seem to fit the bill well. (I hasten to add thought that I haven't actually had the chance to read it personally!) It was written in the early 1950s, but has a "modern" focus, starting from Adam Smith and continuing up to Joeseph Schumpeter.
If you look at this book on Amazon it will link you to a number of other books on very similar lines. Especially if you want something more up-to-date (not to suggest that Heilbroner's is in any way outdated), it would be well worth browsing through those.