It is not uncommon for pregnant women to have different sizes of belly bumps at 36 weeks. The size of your belly does not necessarily indicate the size or health of your baby. Several factors can influence the appearance of your bump, including your body type, muscle tone, and the position of the baby. If you have any concerns about your baby's growth or well-being, it is always best to consult with your healthcare provider who can assess your specific situation through ultrasound and other tests if necessary. Remember that every pregnancy is unique, and as long as you are feeling regular movements from your baby and there are no other concerning symptoms, having a small belly bump should not be a cause for alarm.