Spotting

So I don’t usually have spotting, and I think that it may just be because I missed my pill for a couple days. But usually when I miss my pill, as soon as I start back on it the bleeding stops immediately. It hasn’t. During the time frame that I had missed pills, I had unprotected sex - granted he did always pull out, but I know that isn’t a reliable form of BC.

Is 3 weeks too early to see spotting from implantation? It’s been spotting for 3 days but getting lighter each day.

Thanks.