Its most likely a light leak
When I purposely stressed mine I took it out of the closest for a day.
I do that week 2 of flower.
Take it out for a day a couple times a week unroll week 4.
There are lots of methods that work .
It can be done to clones just as easy.
It dosnt mean bad...
Most plants will produce male flowers if stressed.
So the possibility is in the genetics anyways.
After you stress to get seeds you grow in perfect conditions= no stress= no hermie.
If your constantly getting hermies....you have a light leak.
I'm forcing a plant to herm now so when I saw the picture all I thought was "lucky duck"!!!
That's good pollen brother.
If you can get the same strain sometime in the future you have the capability to have dozens of S1 seeds.