it is usually gas. We think babies that are a few weeks old smile but it is usually just gas which is absolutely normal.
Where you live are there support groups for new moms? Most cities and towns have them and they are great. You would be around new moms and will gather all kinds of useful info as well as make some long time friends with women that have children the same age as yours. I believe you would benefit a lot from these groups. Also if there are community health nurses around they are always very helpful.