Hi Hun,
I had exactly the same as you. Pink discharge/blood at 8 weeks when my normal period was due. My heart was in my mouth when I first saw it...so know exactly how you feel. I didnt call my midwife as I understood what it was and unfortunately, I knew that IF it was the start of a miscarriage there is nothing the medical staff would be able to do about it.
That was several months ago and our little baby was fine....so fine infact, he is still in my tummy and refusing to move at 41 +1 weeks pregnant. If you want to put your fears at ease, then call midwife, but if it is very light, pinky colour with no bright red clots or pain, you will be absolutely fine xxxx