Need help with period question?

me and my ggf have been ually active with condom for 3 months and last month her period was 3 days early this month it suppose to hit tommarow but she has no signs of her period aand she has a feeling of food sitting in her neck when she eats. she also says she cant feel it coming on. so any ideas as to why? we cheak every condom and none of them have broken