first try at keg co2 connect ?

I got a keg filled at local brewery. Ball lock. When i connect the coupler to the in line on keg it started spitting beer. So i pulled it off cuz i dont want beer all over girlfriends carpet. My first try at kegging. Is this normal? Or is maybe keg too full or they put the posts backwards? It is the in line with the sprocket.

The gas in posts have notches on the nut if that is what you are referring to.  Google search for pictures of corny keg posts and you’ll see.

Is the IN post on the side that says IN (sometimes they just have dimples on the handle on the In side, rather than the word In)

If the posts are right and the tubes inside are right, then the keg is a little too full

Ya it’s probably a bit too full. I spent a few hours yesterday fixing the fridge that I messed up. Later today I’ll take the co2 tank & keg to the garage to get it hooked up, since it’s my first time. I’m sure it will be fine, or maybe I’ll get a beer bath. THanks!