Hello Welcome to HCM. I have gone through your description. You have mentioned that you felt the vitamin pill not going down your thrust but into your wind pipe. Did you have any symptoms during that. Any food or foreign body that goes into the lungs causes a very severe cough during the episode. This is a defence mechanism of the lungs to protect against aspiration of foreign bodies. The cough persists for sometime and if the thing is not expelled with cough then it settles down blocking one of the smaller airways. This may lead to chronic cough, recurrent infection and pneumonia. If it blocks the smaller airways, and there is recurrent pneumonia then it can be removed with the help of a procedure called Bronchoscopy which removes the aspirated body under video guidance. As in your case you have not mentioned any severe cough while swallowing the pill or any chronic cough or recurrent lung infection thereafter, I do not suspect that you have aspirated the pill into your windpipe. So unless you had the above symptoms there is not much to worry about. Wishing you good health Regards