Chord Progression

I was messing around with my guitar and I did a chord progression that went like this: Em-D-G-A. It sounded kinda cool to me, but when looking it up online, it seemed to bring up very few if any hits. Correct me if I am wrong, but it seems like that would be ii-I-IV-V in the key of D? Is this a common progression and just something that google wasn't bringing up much? Thanks.

Am, G, C, D

That progression would probably give you more hits. It's the same exact thing, just transcribed to a more popular key...

Technically, you are wrong. You are playing in E dorian. Check out (I think it's Jazz's) lesson on modal theory, it will explain why it's not really D major, and E dorian.

The Am-G-C-D progression - would that also be Dorian, but just in the key of G?

Yes, it would be A Dorian