Brown in my panty liner

Kelsi • Struggling on this journey called “Life”
I took plan b about a week ago and I'm waiting for my period in 6 days. I've been having dull cramps. I feel them but they are light and don't hurt. Yesterday and today I noticed a light brown fluid in my liner. It's not a dark brown but it's also not a light brown. Any ideas on what it could be? Should I be worried?