Baby #2? HELP!

I am due to start my period today, I’m a stay at home mom with no help so I don’t get to do my logs much, but me and my husband has sex the week of Valentine’s Day but don’t know exactly which day. I am now spotting very lightly the day I’m supposed to start my period. No cramps, no sore breast, no signs that it is AF. Could this be implantation or something else other than my period?