Congrats on the new baby on the way, you will love being a Dad. I know I do. As far as selling your gun, I sold 4 hand guns and 2 rifles back in the mid 70's and have regretted it to this day. That being said, family comes first over material possessions. Your job at wal-mart isn't a real high paying job is it ? You do want and need a better job right ? You do need a car don't you ? You do have a baby on the way right ? The answer to those questions should tell you if you did thew right thing selling your gun.
Down the road you will probably buy another gun and maybe a better one than you had and one you even like better. Take care of your wife and the new baby, there is nothing like having a family.