Missed AF and TTC baby #3!

Megan • I`m a mom of 2 beautiful girls and expecting my third baby! I`m young and love cooking, makeup, and dancing.
The past 2 weeks I have been feeling a little off. Been dizzy, feeling nauseated, tired more than usual and getting these crazy headaches! My last period was November 20th. Within the last 2 weeks I did get tiny streaks of spotting and it came out with brown discharge. I started taking Prenatals right away just in case. I took a test today and it came out BFN. I was supposed to get AF today. Am I testing too early? If so when should I take a test? Usually I know when AF is coming but I haven't had any symptoms for it coming.