Someone help my paranoia.

Sarah • tml. 💍 | klg. 👑 | ejl. 👼🏼 | hal. 🌈 | fmcl. 🦁

Okay so I’m 5w, 4days and I just went to the bathroom and there was brown discharge when I wiped, now I know that usually means it’s old blood but WHY.. what causes this? It’s never happen before with any pregnancy.