Perot xnmpak

Assalammualaikum n salam jumaat wt ibu ii di cni...sy nk tnya,adkh normal perot still xnmpk walaupun dh 16week??sy preggy ank third..masa ngndungkn ank no 1&2 klu 16week dh nmpk dh..coz msuk 16week dh nk msuk 4kli scan perot..takot pulk sy..