I drive a 1997 ford expedition. Anyway, one morning last week I left in a hurry and inadvertently shifted into 2nd gear instead of Drive, and I didn't realize it until I was accelerating & I noticed the gears weren't changing. I slowed down almost to a stop before I shifted into drive, and I was wondering, if for any reason I needed to shift between Drive, 2, and 1, would it hurt the transmission if this was done while moving because it is an automatic? Thanks

That all depends on how fast you are traveling... assuming you aren't shifting into a gear that would result in an inappropriately high engine speed (I.E. dropping to 1 from 60 mph). Otherwise in the situation you described you could have simply put it into drive.