Sick baby?

For the past 3 days my baby has been very congested and having a little trouble breathing. I've been using saline and suctioning out as much as i can... but it doesn't seem to be helping much. Ever since he's been congested he has been eating less. He is 9 weeks old and 10 pounds.. so according to his weight he should be eating about 25 oz in a day. He has been eating 1-2 oz every 2-3 hours. He'll fall asleep after the 1 oz and then sleep for up to 3 hours. Could he be sick with something else? Or is this normal with a congested baby? Any advice?