Clearly the OP is just mistaken and misinformed.
Suyadii, please consider that breeding bettas is unlike breeding most other fish due to the unique behavioral aspects of these domesticated fish. For the last 700 years, and probably even longer, bettas have been selectively bred over thousands of generations to be nothing but effective killers of their own species. Humanity has ingrained this violent behavior within them, so the idea that putting two together will get them to breed "as they would in nature" is a moot point.
Consider the American Pit Bull Terrier, while it is a terrible and sad fact, many of these dogs are being bred today for dog aggression. These dogs are so violent that the breeders have to put the female in a special device in order to prevent her from killing the male. We have to take the same precautions with bettas as we would with dogs, except that we don't have the same tools to work with, so instead, the bettas have to be conditioned for weeks to increase the chances of spawning and to decrease the risk of death by exhaustion and starvation, especially for the male, who will not eat after the spawning until his fry are free swimming.
The small enclosure Thai method is only for the most experienced breeders. Their stock have been conditioned and they have the experience to know when the pair will breed, and when they will only injure each other. Pet stores are full of extremely ignorant people--the little training they get is focused on how to sell you products, not great animal care. The simple fact is, the store makes a higher profit off of those little dinky plastic made-in-china "betta tanks" than they do the larger and more simply constructed glass tanks. They don't care if your fish die--that just means you come back and buy more fish and medication and supplies from them. You were fooled. All of the people on this forum don't sit around telling new members lies just for kicks, we're all trying to help you and your fish.
Your male and female were not properly conditioned. Conditioning gets them both "in the mood" to spawn, and triggers the female to start producing eggs. This is a complicated process that will not just happen by throwing the two fish together.
Please get a different container and separate your fish immediately. Once you have done that, I highly suggest researching the care needs of betta splendens. This thread is a good start: http://www.bettafish.com/showthread.php?t=49160
Don't let ignorance and bad information kill your fish and ruin this hobby for you.