For us, fourteen days of theme park is too much.
I love WDW and US, but eventually the experience wears thin.
One of the first things that wears thin is the experience of eating in WDW. I start to resent high prices, long waits, cheap ingredients, limited choices, and especially the lack of fruits/veggies. A bacon cheeseburger is okay on day one, but come day three, I'm craving healthy! Good luck finding steamed veggies in WDW! WDW veggies come in micro-portions coated in grease, HEAVY salt, and/or heavy sauce!
The food over at US is slightly better with slightly better prices. Still, by a wide margin, our recent best Orlando meals have been the ones we ate offsite! (food quality and value!) It is saying something to rank the airport meal as #1!
We expect lines for attractions, but get tired of lines all day: bathrooms, coffee, fixing a non-working magic band, park entrances, bag checks, and every afternoon/evening another parade clogs all the park pathways!
The walkway between your room and the bus stop/food court will always be the most convoluted indirect path possible!
I don't mind some walking, I just crave a few short paths.
As others have said, WDW is much walking. I think you'll discover you want some shorter days. Except guests are no longer allowed to skip ADR's without a fee! Getting across WDW for an ADR can be a long journey!
Then there's the antics of all the other WDW guests: folks too lazy to flush, line cutters, people who shove, people who don't watch where they are going, folks who stop at the top of the escalator, folks who don't think ahead at all. You'd think everyone waiting 20min. in line at a Quick serve would take a moment to READ the menu, right?
You only give us the basics....but to be blunt, your health is more important than your age. All ages do well to take daily 30min walks to prep for WDW. You'll also do well to invest in quality walking shoes. One little blister is all it takes to make for a very long day!
You also don't say how much you like thrill rides, Harry Potter, shows, etc. Some folks tend to focus on thrill rides, others are happy to focus on expensive meals, and shows. Some folks could careless about Potter, others could spend hours in that small part of US. WDW rides are more about story than thrill. US is a bit geared towards thrill, but also story telling. Without kids, you might find the kiddie rides dull...though it sounds like you are going with the idea of seeing all WDW has to offer.
Still, if this is your first visit, unless you are coming form a very long distance...I think nine days total of theme parks is as long as I would suggest. Our happy limit is about six.
