Should I be worried re: my teens clubbing of her toenails? She's 15. Fingernails are ok. Bad Headaches too. She was born with a heart murmor. Told at age 6 months it was fine. Brother did have a large ASD and had surgery at age 3 to repair the hole in his heart. 

She has a history of stomach issues - nothing serious, but what my grandmother would have termed a 'nervous stomach'. 

She now has severe headaches daily. Pain her her neck daily. 

Recently was severely dehydrated (in the winter - Dec 9th).Just woke up one day with with severe nausea, fever, vomitting and SEVERE headache, high WBC count. Required IV fluids. Fine the following day.

But continues with daily headaches and neck pain. 

And I JUST noticed yetserday that her toenails are 'clubbed' (the nail curves around the end of the toe, because the toe is really large and fleshy). All her toes appear this way. Her fingernails appear fine. 

I knew that clubbing of the fingernails can be a clinical sign of an underlying disease, but what about toenails?

I do not know if I am being silly to worry or if I should take her to the doc?

Summarized question: Is clubbing of the toenails a sign of underlying disease?