Has my gluten-free beer gone sour?

[Rachel]

I attempted a gluten-free shock-top clone:

3.5 lb briess sorghum
1/2 oz german perle
3 oz OJ
1/2 lb honey
1/2 oz sweet orange
1/2 oz mt. hood
5.5 grams yeast (used Fermentis Safale S-04)

Brewed on 11/13, OG 1.074... tasted very sweet and orangey, very obvious honey notes, barely any hop flavor.

Tasted on 11/20, Gravity 1.020... tons of orange flavor, no carbonation, sweet with lots of honey... did have the sorghum after-taste

Decided to dry-hop it, hoping to balance out that mineraley flavor. Otherwise it was delicious and sweet when we tasted it. Used 1/2 oz of Mt. Hood that had been stored in the freezer (pellets), and just dumped them in.

Today (11/22) when we tasted it, the beer tasted sour, almost as sour as lemon juice. It was a little carbonated too. My girlfriend said it smelled "off." It is definitely not as delicious as it was two days ago. The gravity hasn't changed.

So my question is... could my beer have gone bad in two days? What could have caused this? How do I know if it's sour because of a lacto infection, or if it's just sour because that's the way it's maturing to be? We didn't see any weird stuff growing on top, didn't get any "gushing," although the airlock did bubble a bit. How do you tell if a beer is "bad" sour, or just... sour?

 

[Double_D]

"Bad" sour is relative to your perception. Did you get a pelicle? It should take longer to get one of those though so just wait. If everything went in at the end of the boil it can't be the ingredients. Maybe something fell or blew in when you took a sample? I've gotten wild yeast that way a couple times. The plus side is if it is sour you can just let is age and come back to it in about six months to see how it's tasting. It won't make you sick drinking a sour beer.