I think if you find the fear is uncontrollable that it might be worth seeking counseling. It is still early days for you, but if it is affecting your ability to function and interact with others it might be worth considering. The Cancer Council is a good place to start. They have phone counseling which many women have found helpful at different stages of their treatment.
It is ok to feel scared and sad but you don't want to spend too much time feeling like this. It won't do you or anyone around you any good. Sometimes you start to feel more in control once you start Chemo. I found it helped me to just focus on what I could do to help my body cope with treatment. I found exercising (I walk on a treadmill) to loud, inspiring music helped to lift my mood and keep me positive. I just kept challenging my fears. Hope you are feeling better soon. It is an emotional roller coaster but you don't want the down slopes to go on too long. Take care. Deanne xxxooo