Positive test, light brown spotting

I just found out yesterday we are expecting :) last night and this afternoon I noticed a very small amount of a light brown discharge when I went to the restroom. Probably smaller than the size of a dime in my undies. I'm pretty sure I am 4 weeks 2 days. No red, no cramping, no pain. Definitely have also felt morning sickness in full swing today. Should I be very worried something is wrong? I found out later yesterday and still haven't been able to call my obgyn since it's the weekend. Any advice is greatly appreciated!!