why does my 22month old boy whine everytime i get home from work?

Most young children will whine right after seeing their parent(s) come back from being gone.  They are normally upset that they were left behind and that is their way of telling you.  At that age, your son cannot express his feelings and emotions very well verbally so he is letting you know he doesn't like what happened.  I would try spending more one-on-one time with him right after returning and letting him know he is loved.  I especially see this type of behavior when parents run out while the child isn't looking in an attempt to 'skip out unnoticed'.  I always try to tell my children when I'm going out, I love them and Mommy will see them soon, followed by lots of hugs and kisses, (they are 32 months and 10 months) and they rarely whine unless they are incredibly tired.