It looks like 1 dry branch, don't worry too much about it, search on google for "cannabis bud rot" look up close, i can't get a clear look in these photos and videos, if it looks exactly like bud rot dispose of that branch before it spreads and controll humidity.
SEARCH IT ON GOOGLE FIRST, I CAN'T GET A CLEAR LOOK AT IT.
Good luck growmie, best of luck ✌️