Can't get all the needed Calories in.

I am trying... I am making notes and making sure I am eating healthier.
However I was not able to get the full 1200 calorie count into my system yesterday. I managed 966
Will I still be able to loose weight.
I was full and stopped eating at 6pm.

Let me give an earlier example of my eating habits. Not counted...
Loads of water never counted before
Breakfast at 10am toast with sweetcorn and milk
eat during the day whatever was in the house.
supper whatever I made for the family
late night...

Can't get all the needed Calories in.