The questions were: is it considered "short selling" if you buy MORE of a security at a lower price? The answer is no -- you're just adding to your position. It's only a short sale if you sell it short, which you're not doing, you're buying stock not shorting it.

The other question seemed to be, does buying lower incur tax consequences? Not if you're buying and holding, because chances are you'll be selling it higher, so you're not selling it at a loss, so, not wash sale stuff because that involves taking a loss.