I was spotting 3 days ago only one day. took a positive pregnancy test today. was that implantation bleeding?

Maybe: If you have a positive pregnancy test and experienced bleeding then you need to see an Obgyn. Bleeding in pregnancy is common but not normal and requires an evaluation.

Spotting in pregnanc: No that was not implantation bleeding. Pregnancy tests are not positive until at the earliest 9-10 days after implantation. It is not unusual to have a little spotting early in pregnancy. If you have more bleeding than that you should be seen and evaluated. Congratulations.