I'm confused

So I'm cd24 and having some dark colored spotting. Looks like pre-period but I usually don't get this until the day before my period starts. And that's not usually until cd27/28. I think it's too late for implantation though. I'm just confused all around. It's kind of an orangish brownish color. Idk. I just want to know if my period is going to totally ruin my vaca or not! Ha!