Antibiotik cephalexin monohydreate

Hi,i'm 9 week preggy now.yesterday i has going clinic and dokter said i have urinary problem in my urin.so,she decide to give me antibiotic chepalexin to take for 1 week and must eat 2 tablet for 3 time a day.may i know,can i finished it?or stop it?coz im worried about my prengancy.thank you.