Chronic purple fingernails

Hi, I'm trying to find out the cause of this. One and a half month ago, I overexercised (went running a lot more than I was used to) and when I finished, my fingernails were purple/blue. Since then, they have remained purple. A week after that I started developing many other symptoms which I'm quite sure have to do something with that.
I went through several tests including EKG, echocardiogram, xray, spirometry, CT scan and blood work. All came back normal.
My fingernails had never changed their colour before that incident. What can have gotten wrong after overexercising? I have been told that it might be raynaud's, but as for my understanding, the colour of my fingernails should be normal except when I'm having a raynaud attack. My fingernails are just purple all the time, chronically.
What other tests can I take to find out the cause? What specialists can I see? There must be something you can tell me. Please, any answer will be highly appreciated. Thanks.

[Paderla Anitha, DNB]

Hello and hope you are doing well.

The blue fingers could be due to an allergen. It could also be due to circulatory problems, temperature problems or a rash. You will need to see if any allergens are triggering this reaction. You may also need to notice if cold is precipitating/worsening your symptoms, to rule out Raynaud's.

Hope this helped and do keep us posted.

[character28]

Hello Doctor, please check this out, I've attached pics here http://www.medhelp.org/posts/Undiagnosed-Symptoms/What-do-you-think-about-this-permanent-discoloration/show/1818448?personal_page_id=2770133