If i eat a fruit that isn't a sweet, but i eat the same fruit days later when it becomes sweet, do both of those fruit have the same no. of calories?

Same # of calories: A fruit will contain the same number of calories whether it is ripe or not. The difference will be in the sugar content. As a fruit ripens it converts more of its structure to sugars. This is important to diabetics who have to carefully monitor their sugar intake, but not to a healthy person. Fruits (ripe or unripe) are a good source of vitamin C and fiber and part of every healthy diet.