Thanks for the reply!
Just to add the history of my condition... I had my first reaction after eating a cashew nut when I was around 5, which left a very horrible taste in my mouth (From my limited memory). I recall there being a big fuss, and eventually my mum's friend came over and drove me to the hospital where I was told I had a nut allergy.
Since starting this thread, I retrieved my medical history from my doctors, and I last visited an immunolgist I 2002 where the certainty of my allergy was deemed as "Likely" and the severity said to be "Severe" - Unfortunately.
Since then I've had one occasion of eating Cashew nuts by mistake, and when I realised (Very quickly), I had a really itchy mouth so I took the epipen there and then. But it's hard to say exactly from that experience, especially as it was maybe 7 years ago!
What's even more weird is that I eat peanuts all the time, and I've accidently had hazlenuts, almonds and Pine nuts without any issue.
I do now have an initial class one medical booked, and was told I could end up with an OML (or worse)