My nails have taken shape of a parrot beak . And the  skin area below the nail is become black and fat. I have done some test which were shown online like the diamond shape test (window test) and the results were negative. Also I have recently noticed that the thumb nail has got a black(brownish) strip running through the nail. And i don't know if this is relevant , it's been a while now (4 months ) , my stomach becomes really acidic soon. ie. After lunch the stomach becomes really hard and fat. What can be the cause of all this ? What precautions should I take ?