5 days late and implantation bleeding?

So my period is 5 days late today and I'm always very regular. But today I noticed some light pink blood so I thought it might have been my period but it's not enough to even require a pad or anything. And now after just going to the bathroom again I noticed it's started to be this light brown discharge/blood.

Is there a chance I could still be pregnant and this is implantation bleeding? Or is this most likely a very strange period?

I truly appreciate the help!💖

Also-- I took a test 6 days ago and it was negative but I'm wondering if it was just too soon (it was also in the evening)🤔

EDIT; Aunt Flow came with a vengeance, so I'm out for this month. Ah well, always next month!😊