Help me please?

Has anyone experience spotting while pregnant? I'm 15 weeks pregnant first I had that clear discharge n I know that's normal then I had brownish discharge witch I know that normal as well Cuz I already have a baby! Bt scents Friday I've been having pinkish spotting no cramping nothing painful, went to the hospital n they told me that I n side my placenta there's a bruise and that's Wats is making me bleed it went away n now it's cuming bck.. should I worry?