pink tinged discharge?

Michelle
Ladies, I'm 6.5 weeks and have had two episodes of pink tinged discharge- very small amounts, maybe a fingertip worth in the past 24 hours. 
No real cramping associated with it, just a full, bloated feeling. 
I did about 4 hours of walking yesterday at a museum, which is more continual activity than I'm used to. 
I have an internal ultrasound tomorrow. Should I mention this to the doctor?