Implantation Bleeding?

Estefania

Me and my husband have been TTC for the second month now. I got my period 4 days earlier than the usual and it has also been really light. My bleeding comes and goes for the past 3 days. My periods last 5 days and this being the third day I haven't been bleeding at all but a couple drops or when I urinate. Could this be implantation bleeding. Really hoping for a positive pregnancy test before Christmas. How long before a test can detect pregnancy?