Could it be implantation?

Miranda

Hi. So I’m already a mom of 1. My cycle is pretty consistent and never changes. Recently, on June 28th, I had unprotected sex. A week later, I started to spot very lightly. It was light pink to brown. It never got heavier. Then, it just stopped. I’m so confused this has never happened. What could the spotting be? Could I have ovulated earlier than usual? I don’t know. Any help and advice is appreciated.