Battle.net

i started out playing the story mode then at some point it kind of quit on its own. i dont know how to get back to it. if i click single player and click continue, all it does is bring up mission archives, where ive completed them all.

however in the achievements spot, im only 20% done. am i really done? is it that short? i just didnt get all the achievements?

so have i done it all, just on casual, and the only way to do more is different difficulty?

if so, seemed so short

There are a few optional side missions that you probably have not done. For instance if you chose to side with Hanson, you probably haven't done the the other mission, or found the secret mission. If you in fact were on casual that could be part of the problem why it was so "short." Casual is ROFLSTOMP easy and you probably sailed through with zero resistance.

Looking at your profile I'm guessing you ran through the campaign on Casual difficulty. You don't have any credit for mission completions on Normal or above. That being the case, after you beat the campaign, regardless of difficulty, whenever you opt to continue a campaign ( that has been completed) it always starts you at the Mission Archives.

If you're lookin' to go through the campaign again, just fire up a new one.

ツ