how to know if this is a brown discharge?

Hello, I'm in my week 13 and have the same brown discharge as you. I went to KK A&E last Saturday, and after having progesterone pills for 6 days , I noticed my brown discharge coming back again the past 3 days. I went back down to KK A&E today they did a vaginal swab for me and do a ultrasound to check on my baby. Currently waiting for the result to see if it's vagina infection. I was told that red or pinkish colour should be a cause of concern. if you are worried you can check with your gynae.

Mine started around week 18, on and off until now (week 24). But no pain or anything. Asked my gynae in my week 20 checkup and she did a vaginal swap test but no infection or anything. So still dunno why 🤷‍♀️ But I notice it always happened when I walked too much the day before or bent down. Not sure if it is the pressure on the lower abdomen🤦‍♀️