Hay, congrats sa 20 weeks! Honestly, brown discharge during pregnancy can be normal sometimes, pero since you're a first-timer and it's been consistent, better to mention it sa OB mo next checkup para sure lang, brownish discharge can mean different things at different stages, at sige na, peace of mind talaga ang kailangan natin as moms, diba? One of my mum friends had something similar and it turned out okay, pero it's really best confirmed with your doctor directly kasi they can check properly. In the meantime, just keep an eye if may cramping or bleeding na sumusunod, at if it gets worse or may unusual smell ulit, don't wait, message or call your OB agad!