Hindi ka mag-worry, mama, bawat pregnancy talaga ay different, at ang laki ng belly depends sa maraming factors like kung ilan na ang babies mo, body type, at kung paano ka nag-carry! At 25 weeks ka pa lang, so may time pa for growth. But honestly, kung concerned ka talaga kung mababa or okay lang, better to check with your OB next visit para ma-measure nila properly yung fundal height and ma-confirm lahat ay normal with the baby. One of my mum friends nag-worry rin siya about this, pero sabi ng doctor niya fine lang lahat based sa ultrasound, so definitely ask yours na lang to ease your mind!