Really nervous! !

•Jade•
Why is it I thought nothing of testing at 6DPO, but now I am 12 DPO and getting ready to test tomorrow (if AF hasn't reared her ugly face by the morning) I am really nervous!?! Every time I think about testing my stomach does a little summersault at the thought of it. 
​Is it nerves in anticipation for the BFN I feel I am going to get? All day today I have had the feeling that AF is just around the corner but she hasn't surfaces yet. 
​Anybody else testing tomorrow and feel the same?  
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