Trying to lose weight

Not sure why today i am tired and craving chocolate.
Yesterday was a good day, with great energy and eating.
I am not sure why today is different? Not enough sleep? Perhaps the drink I had yesterday that contains sucralose. I think I figured that aspartame in Costco diet iced green tea and propel zero have that affect on me. So now I will stay away. I also have aslught headache now towards afternoon/evening.
I gave in to cravings nibbled on dark chocolate during day, a little bit coconut flakes and macadamia nuts as well as quest protein bar in pm. Not a great day.