What’s going on ?

I’m 6W4D today . The other night I woke up to urinate and after that I had this pain behind my belly button then I got this SHARP pain in my butt. It had me up literally all morning. About around 6 I wiped and I saw a little pink blood and after awhile it stopped. I made sure to call my OB and they put me in right away. I went in and they checked me and all said everything looked fine and they even let me see my babies first ultrasound. Today when I wipe it’s really normal discharge with the smallest little pieces of pink in it .. what does that mean ? I’m a first time mommy .. so I’m nervous