21 weeks preggy and yet nasusuka/naduduwal parin

Hello mommies, 21 weeks preggy ako with a baby boy. This is my 3rd pero I only have 1 living child (daughter) kasi namatay first baby ko (son). My concern is.. for the last 2 pregnancies I had, kung kelan nasa 2nd trimester na ko super duwal at suka ko parin. Sino same sa case ko? Is this normal?