sour beers, gravity, and carbed samples

So I have been taking gravity samples for my lacto brett golden sour ale wit saison american wild... wellx you get the picture. The gravity has been stable across two months, and the beer is where I need it to be flavor wise. I noticed that each sample I took was slightly carbonated. I am not used to seeing this in my samples of other beers. My pales and stouts tend to be still, so I am tentative about bottling at this point. Is it normal for a sour beer to have a touch of carbonation after fermentation is over?
also, the last three readings have been 1.007.

 

6months.