implantation bleeding or birth control

last month 8 days before my period i started brown spotting which quickly turned heavier and had some fresh red blood mixed in, this bleeding continued four days into my inactive pills and stopped. I had some cramps the week before my inactive week but not during it. now i am onto my next pill pack and have had nausea and cramps for the last three days, is this normal? (it’s only my third month on the pill btw)