I have an Aquarius moon in the 5th house isn't that an oxymoron?!

I have an Aquarius moon in the 5th house isn't that an oxymoron?

Not really, though I understand why you would think that with aquarius ruling the opposing house. The signs show the way in which the planets express themselves and the houses show the area of life in which they are expressed. Your aquarian moon would express itself in creative pursuits, games, fun, and romantic involvements.