No it justs means it is preparing to mate and have children with a female betta fish
Female Betta fish will have an “egg spot” aka the ovipositor tube, when they’re older than 4 months. The egg spot is a good way to identify a female and tell her apart from a young male. The egg spot is a white dot, located near the base of the ventrals. It is from this egg spot that eggs will be released by the female during spawning.
Bettas should be fed what takes no more than 2 minutes to eat. If they really like what you are feeding them probably less. Wild instinct tells them to eat as much as they can. Being that we know when their next meal is and they dont, we have to control food intake. Fat and obese fish loose points in betta competition and can be unhealthy to the point where over conditioning them is negative. Female fish can actually become somewhat infertile because they cant release their eggs due to internal problems. Plain and simple, dont over feed.
Male vs. Female; which to choose? - Betta Fish and Betta Fish Care
Why do male and female betta fish fight in the same tank? - Quora
Myth: Female bettas need other females for company and will become lonely and depressed without others of their kind. Reality: Anthropomorphism is a grave enemy of fish. Bettas are a solitary species; they do not need companionship and will not become "lonely" or "sad" without the company of other bettas. Overall, other bettas simply create territory disputes and a need for a pecking order. Sorority tanks can be safely formed, but please understand that it is done for the owner's preference and not for the needs of the fish involved. Those wishing to keep social fish would be well advised to consider a schooling species instead of bettas. Myth: Bettas are completely unsuitable community fish and can only be housed solitarily. Reality: While the safest way to keep bettas is solitarily for both the betta's sake and that of its would-be tank mates, it would be inaccurate to suggest that bettas can never be housed with other fish. Placid males and females can often be housed in a well-planted community tank with mellow, dully-colored fish, as well as some aquatic invertebrates or amphibians. Careful monitoring is demanded, and the positives and negatives of the housing situation should be thoroughly evaluated prior to mixing species, but the community betta is not an impossibility. Myth: Female bettas are peaceful and can always be housed together or in tropical community tanks. Reality: Many female bettas are equally as aggressive as males - with added speed and mobility due to their short finnage! Sorority tanks are only possible in a well-planted environment under highly specific population and gallonage conditions, and even then injuries and deaths are commonplace. Likewise, female bettas will often attack and injure community fish, especially ones who resemble bettas. Male and female bettas are almost equally solitary; the safest way to keep females, like males, is alone. If you do wish to keep a sorority or community tank with females, you must monitor closely, and read up on setting up such a tank safely. Todays topic is going to concentrate primarily on the less desired female Betta fish. The female is not nearly as popular as the male but strongly holds other benefits to owning it. I have personally owned these fish for years and have a deep passion for them. They are less beautiful than males but can be schooled up and hold many other desirable traits. Please excuse all grammar and punctuation errors. After all, I am an aquarium geek and not an English specialist.