Is this positive?

I haven't experienced exactly that, but spotting can mean different things at different times, so it's really best to do a proper test or see your PD to know for sure rather than guess lah. Since you're already 4 days late, a home test should be pretty reliable now if you haven't tried one yet. A few of us have had confusing spotting situations before and it always helped to just get checked out so we could stop wondering and know what's going on.

When it happened to me, the spotting only lasted a couple of hours each day, which just confused me even more. I finally went in to get checked just to be safe, and everything turned out fine—it was just a random hormonal blip. If it keeps playing on your mind, it might help to chat with someone. I usually go to Dr Chris Ng at GynaeMD, and he's always super reassuring and puts you right at ease.