I’m so confused 😕

So I’ve had a couple faint positives, then started a brown spotting. My Dr says he thinks it’s either a very early pregnancy or chemical pregnancy. It was a pinkish yesterday when it first started but now it’s a dark reddish/brown. It’s not a lot at once, obviously for hygeine reasons I won’t leave the pad on anymore than a few hours. But I don’t fill them. Dr thought yesterday it might be implantation bleeding. The last time this happened I was pregnant with my oldest. But the only thing is everyone says that starts before you’re missed period. Mine was late before it started. I’m so confused help me!