Brown Discharge after 17 Days of ET

Hi 👋 I'm currently on my IVF journey and I'm at my 17 days after embryo transfer. This morning I noticed brown discharge on my pantyliner. I'm not sure if I need to be worry about it or it is just part of the process? This coming Monday is THE DAY for me n husband. Blood test result that's gonna determine if we are gonna be parents. I just can't help to be anxious about it. Does anyone experience this before? Help!