I've been diagnosed with bad intestinal absorption. pain in one of my nails, it had some erosion and then started to break; it was yellowish as well. i had to change my diet, but now the nail is clubbing. also, have dots on other nails. can you help?

If you already have a history of abnormal absorption, then this sounds like a nutritional deficiency and/ autoimmune disorder (GI/ lung/ rheumatological). I would recommend that you have your primary take a look at your nails and you may need to see a specialist for further evaluation. If you smoke - stop, as this could be another cause for your symptoms.