Well, you should trust an intact condom. Pregnancy happens with condoms when they break and you know when they break as that is a catastrophic event. Pin holes are a myth. So, you are likely just late. Women are late for many reasons including changes in routine, stress, weight gain or loss, illness, new exercise routine, or just a blip in the hormonal radar. Pregnancy tests are usually accurate 2.5 weeks after sex, but really, you are most certainly not pregnant. good luck
Hm. Well, breast changes do happen during pregnancy. But hormonal changes cause it too. I would not use this to judge pregnancy though in any way. Did you have unprotected sex? Are you late?