Maybe it's mental???

Courtney
Last night I was laying in bed almost asleep and got so nauseous I was afraid to move... 
After a couple minutes I finally went in to the bathroom and ended up getting sick, no other symptoms or feelings. Felt 100x better afterward. The dinner I had I shared the exact same plate with my best friend and she felt fine... 
I had two different dreams that I finally got a BFP and was trying to find a way to tell my DH....
Woke up Around 5am and took a test... BFN :( 
AF is now 4 days late and no signs of her coming any time soon.
Could I be psyching myself out??
Anyone else have this happen?