How long until I need to take a test after spotting?

Hey ladies. So my period usually comes at the end of the first week in the month, or sometimes a couple days after.

This past Friday I noticed some very light pink with a little faded dark brown on my underwear and a couple times when I went to the restroom..so of course I thought, oh great getting my period early; BUT NOPE that night was my only bleeding.

Could that have been implantation bleeding? And if so, when should I take a test?

Any answers/opinions will help!

Thank you!