Why is there white spots on the edges of my teeth?

I got my braces last Friday (only the top ones, lower one get done after 6 weeks). I noticed a few white spots on the edges of my teeth. I do know that this is caused by not brushing with proper technique or regularly but this is the problem. I brush my teeth every morning and before I got to bed but sleep like after 30mins, i do the correct technique such as the 45 degree and brushing between the gum line and the tooth(I take 20 to 30 seconds in each bracket), i also brush the molars and the back of the teeth then i use the christmas tree brushes on each brackets followed by flossing(i am only been able to floss all my front teeth until where my teeth was take out, 4 2nd molar teeth were taken out by the dentist, after the gap of my empty tooth I couldn't reach the backed my teeth, It took me ages to try flossing it but eventually I gave up, after all this i rinse my mouth with mouthwash for 30 seconds. I now only floss at night because of the time it took me. All the stuff were given by the orthodontists apart from the toothpaste, i bought a fluoride toothpaste separately. I have 3 proper meals that makes me quite full enough not to eat any snacks between the meal. This is what I have for breakfast, lunch and dinner until today and probably will continue eating so. Breakfast: biscuits with tea or hot milk(i put as many as biscuits as possible then I use a spoon to break the biscuit in the cup. It turns out to be soft so I don't have to chew) for lunch: noodles and for dinner:rice porridge, I sometimes have rice porridge for lunch and noodles for dinner I don't like to eat the same dish every same time! After each meal I rinse my mouth with water, sometimes I brush my teeth if I can be bothered. I have been doing researches and I found this is called hypocalcification or due to not having enough mineral or vitamins. I have been drinking enough water but not sure how to eat fruits or am I even allowed to eat them. I also haven't drank any soft drinks apart from fruit squash. Does anyone know what causes this to happen or should I speak to my orthodontists. This is worrying and I don't want this permanent white spots after I take my braces out. Please help me out here!