Cervical Erosion and missing period ??

Patient: 25f married had cervical erosion in the month of novembr doctr asked me for quaterization my periods are very regular till now My last period was Dec13th i had unprtoctd sex last 2weeks back no periods yet i was bleedin a lit bit last week during intercourse next day it was bit brownsh dischrge then stopped im jus worried as doctor told me not to be pregnant during cervical erosion treatment pls help me