I moved around recently. Had my LTD in the guitar for a few days. Finally got to bring it inside last night. And today changed the strings. And the action seems high as shit. I've never lowered the action or anything. And it was always a little high. So I don't know if its because I havnt played in a few days. Or if, like my uncle said. It dried out and the string tension bowed the neck. Is there any way to know for sure?

When you say you had it in the guitar for a few days I'm guessing you mean you had it in a car for a few days? I left a bass guitar in a car for about a week or so when I was stationed in texas a few years back, and it warped the neck so much that the action was almost an inch off the fretboard at the 12th fret. Big temperature changes can ruin necks.

Yes sorry for the typo. I'm no where as bad as Texas. I'm in Northern Virginia. If it is that though is it permanent?

Take it to a luther but if it is bowed you'll need to get a new neck.

Let's cross our fingers and hope it's a guitar with a bolt on neck. If so, simple fix.

First of all, lower the bridge to get the action you want. You should also set the intonation, use an electronic tuner: if it is sharp at the 12th fret (in comparison to open string), move the saddle back; if flat at the 12th fret, move saddle forward (closer to the pickups, neck, etc.).

If you get too much string buzz, you'll need to adjust the truss rod. The thing is don't adjust more than 1/8 of a turn at a time, and not too much in one day (a full turn a day could screw up the neck).

If you put a finger on the last fret and on the first fret, the neck should have some relief, but not too much, less than a millimeter. If it doesn't the guitar has backbow, and the truss rod needs to be adjusted in the other direction.

You can also check if the frets are parallel by looking from the nut down. If it's warped there's not much you can do, it can be complicated to fix even for a luthier.

You might want to do a search on what I wrote about to get more detail (photos, clearer explanations).