Sick female Betta needs diagnosis. What does my female Betta have?

Question

I think I overfed my Female Betta, although I'm not sure that's what it it is. She has been floating on her side not able to go to the bottom of her tank. Her stomach has some swelling, her back looks bent. One of the other females had the same thing, I isolated her from the rest for four days, after the third day I gave her skinless peas and she went back to normal, I put her back in the 10 gallon tank the next day, now the other one seems to have the same thing. The water is perfect, the temps is also perfect, I'm very worried, she seems as if she would be in agony, I treated her as if she would have swim bladder disease. It's been going on for three days. I took her out of the tank and put her in a small "pot" with a bit of less water so she doesn't struggle too much going to the bottom. She doesn't seem like having dropsy, her scales aren't "sticking out". Her scales are fine, she seems otherwise alright, no signs of parasites or injury.

I only have three tanks, a 55 gallon (which has three Pleco's and three Mollies) and two 10 gallon tanks, one for the three female Betta's and one for the male Betta. (The females are not aggressive towards each other).

What does she have? What else can I do? Is she dying? She seems in horrible pain, should I just, euthanize her?

Here are some pictures:

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas1.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas12.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas17.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas20.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas3.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas41.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas43.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas46.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas6.jpg

http://i156.photobucket.com/albums/t17/kKreuz/My fish/reas.jpg

Answer 1

Continue to feed it peas.  It is almost certainly constipation, and the extra fiber in the peas will help to clean out his digestive system.  Brine shrimp would also be a good choice, as they are almost entirely roughage.  If nothing helps after a couple more days, add about 1/4 teaspoon of epsom salt per gallon of water to act as both a laxative and to draw out any fluid that may be dropsy (even without pineconed scales).

Answer 2

Did you try giving her peas like you did to the other beta?