You can't do a whole lot better than zero caloric intake in terms of losing weight as fast as possible :). If you lost 3.5 pounds of fat in 10 days (0.35 pounds per day), i would view that as being pretty great and actually that's about how much fat i would expect you to have lost, given your 140 pound starting point. Your body is burning something for fuel and fat is primarily it.
However, normally we lose a lot of water as well (only temporarily) and i would expect you to have lost 5-10 pounds or more of water by this time, but it seems you have lost very little if any at all.
Are you by chance supplementing with something that contains sodium? If so, that would explain everything. If not, i am at a loss.