I'm Around 8 Weeks Pregnant, Last Week I Went For

I'm around 8 weeks pregnant, last week I went for an ultrasound. I was supposed to be 7 weeks and 4 days but I was only measuring 6 weeks and 4 days plus the heartbeat was only 113. Lash night I started having brownish discharge then later on it became bright red blood and this morning it's starting to turn back to a brownish color. What should I do? I have mild cramping consistently but nothing to knock me on the ground