Brown discharge

Hi ladies! ❤️
The past two days I have been having brown discharge in my panty liner.  No bad cramping (just the normal pulls and pinches) but the brown has me worried. I had this with my first pregnancy, but only after sex. Since I'm high risk this pregnacy, I'm not able to have sex the first trimester.. So it's not from that.  My nurse says not to worry about it unless it's bright red accompanied with cramping. Way easier said than done. I've had two miscarriages since my son was born and I'm worried. Any ideas?