First response pregnancy test had faint positive 6 days before my period should be missed. slight cramping, should i be concerned? period due sunday.

Repeat the test: I would repeat it today. This could be some implantation cramping, which is relatively common. If your repeat home test is now positive then call your OB provider and schedule an appointment sometime for the next couple of weeks and start taking at least an over the counter prenatal vitamin. Sex in early pregnancy also a cause of cramping and spotting