It is normal and should adjust in time. It takes one mile of blood vessels to circulate one pound of fat. As you lose the fat, your body has to re-absorb the vessels. During this time of adjustment, your blood pressure may be lower than normal. My BP is always on the Lw end (around 100/56), however when I drop 5-10 pounds in a month, it will drop lower for a few days then balance back out. I also notice problems with my sugar balancing when my body decides to leg go of a few pounds in a row. I just keep tabs of the cycles and log what I am doing and eating so I can spot trends and notify my doctor if something doesn't feel right. Hope that helps.