I had intercourse the day before my period started and when I had my period it would go away for a day then I would spot then it would be light and it lasted 8 days. I didn't take plan b when I had intercourse then about a week ago I had sex again and the next day I got plan b took it then the nurse gave me birth control And to me to take it the next day and I would expect my period on the forth week and last night around nine pm I seeing I was bleeding and put a pad on I assumed it was my period and when I got up this morning I literally on has two dots on the pad I wore so now on the clean one I changed into I haven't bled can I be pregnant even though I got tested and they were negAtive?