Missed period... Pregnant or stressed?

[Spof3007]

I am now 6 days late for what is normally a 28-30 day cycle. 5 days before AF was due I had a small amount of brown discharge in my knickers which lasted for nearly 2 days. I feel queasy and have been getting crampy twinges and pressure in my lower abdomen. I also am craving anything fish related! Took a test yesterday (5 days after AF was due) one in the morning and one in the afternoon. Both BFNs!!! Is there any chance I'm pregnant? Just wish I could know one way or the other! I have a doctors appt. on Tuesday, just being impatient... It's all I can think about.