Spotting at 21 weeks

Lauren
Hey ladies. I had some extra discharge today and along with it was a slight tinge of brown. Very very minimal but I wiped twice and saw it both times. I called the doctor and they said it's nothing to worry about. It is normal as long as I don't start cramping or bleeding. I'm on vacation and the chance in altitude could have something to do with it they said as well. 
I'm not freaking out but of course I'm definitely a bit uneasy about it! Just looking for some feedback from others who have experienced it. This is my first pregnancy. I'm currently 21+3 and I can feel him moving around and active at least.