Thanks so much for the video! I actually learned that most of the male/female indicators are myth and not 100%. But I liked that he showed the difference in the vent area on both, and especially the rough gills and first bone on the pectoral fins. I’d guess those are the best indicators, but only if you plan to catch your fish to know for sure.
As to your fish, if your closeup picture is of the vent, I’d guess that it’s a male. Did you try putting pressure and sliding your fingers towards the vent to see if white sperm substance came out? If so, it’s definitely a male. And, if it is a male, then I’d guess it has more of an issue than first assumed. BUT, if it’s swimming around and healthy acting, maybe not a huge problem at this time.
One other thing I wondered, but I’m sure you have thought of this, where are you located, and if you are where it’s getting cooler/cold, how long ago did you stop feeding? Maybe this fish doesn’t know when to stop eating …
Good luck! I hope you get it figured out.