L.M.
It makes sense that he isn't interested in eating. He probably has no taste and/or smell. Try some chicken or beef broth (home - made is best) in a sippy cup or bottle (whichever you are using). Remember that he's experiencing a cold like you do... not wanting to eat or drink due to stuffiness and not being able to taste or smell. You can also try Pedialite if you are concerned about his electrolytes and hydration. If this is just a cold, it should pass in 7 to 10 days. If it goes longer than that, take him into his doctor. Also, try a humidifier in his room at night to help him breathe.
Hope this helps! :)