pluck them and double efforts of looking over plants often.
nanners aren't too big of a deal. most of the time their lack of complete anatomy limits their pollen production significantly. A sac is a different animal.
So, is that a lone nanner or a sace that opened with several nanners and a complete set of male organs? Lokos like 2 nanners, but not the best angle. Is there an 'envelope' that opened or are they lone nanners?
you want to catch theses before they are yellow. If they are green, they haven't matured yet.
if it's one plant you definitely keep pressing forward. if it is 1 plant among many you start to weight risks. Maybe, you don't see any more develop, and that's great. or, you see a bunch more and it gets worse, lol. range of factors to consider for best path forward.
can always make bubble hash from seeded weed. (ice water hash... dry ice hash would work too, anything that is a sieving process would be best for seeded weed)