I would trust her instincts.  My son had never had a nut because he was young, but was adamant that he did not like them, mind you we ate them all the time at home.  We were in the car with my sister one day and she was starving so eating trail mix and he pipes up from the back seat saying eww, I smell nuts.  All of this happened prior to him being diagnosed with a tree nut allergy.

My 11 year old was just diagnosed with a tree nut allergy.  Never liked nuts (although she did enjoy nutella as a little kid, about 5- 6 years old we used to buy it for a while)

She has a cousin with a nut allergy, and I assumed that she didnt like nuts because the cousin couldnt eat them...  sort of an empathetic thing. 

She ate a cookie with nuts in January, and got a stomach ache, making me think she might actually have an allergy. 

Then in August \ September she ate products with nuts or that had cross-contamination and got either itchy mouth or vomited.

She tells me that she can "sense" nuts.  Like....  she gets a funny feeling when looking at a food with nuts.  Almost like a gut feeling.

Is this something that happens to a lot of allergy people...  The last time she got this gut feeling, there WERE nuts in a cookie that looked nut free.