Implantation bleeding on the first month, is this normal? We were jus…

Implantation bleeding on the first month, is this normal? We were just so happy about the pregnancy yesterday, but today we have spotting. The doctor said it's "implantation bleeding" and that it's... normal, he didn't explain anything. Still, fear of losing the seventh baby takes over and I listened to half of his words out of fear. It's scary to call, I don't want to hear again that the baby might die and that it's another miscarriage, the fifth one.