What can i do if my eyes are changing colours randomly, what's with this?

Hard to say: The iris can change over time as you gain/lose pigment, pupil changes size, changes in blood vessels etc. However, it shouldn't change from day to day, hour to hour. Sometimes eyes can look gray, other days green--usually it's more an optical illusion from lighting--i doubt it's actually changing. If you truly feel like the eyes are changing, see your doctor.

Not likely!: The color of eyes are mostly associated with iris color pigmentation and sometimes scarring or deposits in the corneas. Changes in color over short time periods are much more likely just from more reflections off of the room lighting or other ambient light conditions. Some hazel, green, or blue eyes can do this more than darker colors. Hope that helps!