I'm booked in to the hospital in 10 days regarding a black

line on your toe nail. I've had it 8 months and put off seeing anyone due to Covid but I went to get a pedicures and they said it should be seen straight away . 
sent pics to doctors and get referred straight away . I know the chances are small but with a family history and they Change in nail I'm becoming worried . I'm not a dramatic person but 5% means someone will get it . 
my nail has gone from one light brown line  to a thick dark black line .