It is completely normal for your belly and breast size to fluctuate during pregnancy. Many factors can contribute to these changes, including hormonal fluctuations, changes in body composition, and the position of the baby. It is not uncommon for women to experience periods where their belly or breasts may appear smaller than before. However, if you are experiencing any other concerning symptoms such as severe pain or bleeding, it is always best to consult with your healthcare provider for further evaluation and reassurance. Remember that every pregnancy is different, and what may be considered normal for one woman may not be the same for another.