IDK if that's a calyx, I see a little branch and its pod shaped vs tear drop. I did not think sacks had hairs on them but some do it seems. I think this is a males sack.
Pluck one off the plant and open it up. does it have smaller pollen like pads in it? If so you need to pluck them all off before they open. like right now!
https://www.growweedeasy.com/pictures-of-male-marijuana-plants
Make a note and check for new ones till its done and harvested, maybe no grow that strain again. I have heard some strains make sacks in first few weeks of flower and if you pluck them its fine, but I have not personally experienced this yet. Just hearsay as of yet.
Good Luck!
