has anyone had bleeding and mistaken it for their period?

Has anyone had "breakthrough bleeding" or experienced what they thought to be their period but didn't find out until later that they were actually pregnant? I'm very confused with my body right now. I'm 3 days late which isn't normal for me at all, my cycles are typically 23-26 days long and I'm going on day 30. However, I got my period last month (or at least I THINK it was my period). Anyone else ever experience something like this and turn out to be pregnant?