Possibility of being pregnant while using condoms?

In sept of last year I unfortunately lost my baby at 8 weeks. I didn’t find out until my 12 week check up though and it was gut wrenching. My husband and I decided To hold off trying again for a few more months bc we moved out of state in November and needed a little bit of time. I didn’t want to start taking BC since we only planned on waiting 5 months or so. We decided to just use condoms instead. Now mind you, if I would have gotten pregnant in the meantime, we would have obviously been thrilled but just wanted to use protection anyways.

So anyways, I’m here bc I’m currently 2 days late for af. I’m usually 30-32 days but today was day 34. Yesterday I had signs of af for sure. Moody, crampy etc. the normal for me. But still nothing. I know it’s completely possible to get pregnant even while using condoms but is it really that common? Has that ever happened to anyone else? I have not bought a test bc I wanted to wait a couple more days and see if af shows. In the meantime I figured I’d see what you ladies thought!