Molly Head Shaking?

Question
I have a 10gal. tank, a Dalmatian Lyretail Molly, a Creamcicle Lyretail Molly, and a pregnant Red Wag Platy. all female. and my red wag and dalmatian were rather aggressive... but once i put the mirrors on they kinda calmed down. i fed them and it kinda came back. not near as much as it was but some. and the dalmatian has been making a rather odd motion with it's body. shaking it's head as if saying no... also, my creamcicle and my dalmatian were fighting a moment ago. not bad. but they were and it was short. (dalmatian started it)
Thank you for your time :))

Answer
Kyle,

Mollies shimmy often when they are sick or stressed or if the water is too cold. Mollies like to have a water temp of around 78 degrees. Mollies also thrive in water that has salt in it. In fact they grow stronger and are healthier if they have some salt in their water. I would get some aquarium salt and add some to your tank as per the directions on the container. When you have added that wait a couple of days and see if that has helped her at all. I am thinking that after you fix the water she will stop the shimmy and go back to being happy and healthy.