I went through your question properly and I can assure you that you must not worry as there is nothing serious in this problem of yours. As you mentioned that these white dots are not painful, they are nothing but some oil trapped under the skin and is very much like whitehead pimples. The first thing you need to do is to clean your penis very nicely and maintain a standard of hygiene. And then also if the problem persist, you can consult a good doctor.