In that case, the factory warranty is done (except rust through and 8/80
emissions components). Be aware, though, that no oil on stick is not the
same thing as empty. In most cases, no oil on the stick is about two
quarts low. As an estimate, pull your stick out and consider each quart
low to take the same length on the stick. See how you only get to two
quarts or so before reaching the bottom of the stick? The issue is that
the dipstick does not reach down to the bottom of the pan. Your engine
holds about 4.5 quarts, so it's not as bad as you originally thought. I'd
definitely keep an eye on it though.
Also check the warranty you purchased to see what it covers and what
deductibles it has. You may be able to get some benefit from it.