I recently joined the 2vs2 ladder, my partner and I have won our first 2 games. The thing is though, when we won we were on 1506, we still haven't lost yet but now our rating is 1489. It just decreased randomly on its own. Is this meant to happen? Does the rating decrease if you take too long on the ladder? we have 2 games on at a given time, just wondering why this happens

Lol i would ask the same for 1v1 ladder....

The ladder rating is based on the strength of your opposition. If one of the opposing pairs had a bad run and took a rating dive, your rating would also suffer. It will be more visible since you have only played two matches and thus have a smaller sample size.

The 2vs2 ladder uses bayesolo Elo as rating method. That means your rating depends of the rating of your earlier opponents not only at the time you beat them, but also later till the game expires. So if your opponents lost a few games, your rating decreases.