Heartburn very early sign of pregnancy?

So

Currently TTC baby #2, I’m thinking (or hoping?) it could have happened for us this month. I’m 8 DPO so waiting a few more days to test, but I have had terrible heartburn the past few days. I had lots of heartburn with my first, but I don’t remember it being this early. Could this be a sign of pregnancy, or do I just need to eat better, lol?

Update: I am pregnant!!