Hi all

After having two moles removed in the past 3 years, one of which apparently the "cells were starting to change and become cancerous" (?) I am naturally nervous.

I have (3 days ago) found this under my big toenail 

I must stress I have an appointment with a private dermatologist tomorrow but I'm just wondering if anyone has any similar experiences and/or ideas? I haven't banged/stubbed it etc. It's not presenting as a melanoma normally would, however docs that referred me can see a couple of small black verticle lines along with the blue coloured spot. 

Going out of my mind a little, please help!

Thank you! x