5 yr old boy crying

My 5 yr old son has always been a high maintenance child.  He started kindergaten this year and to my surprise he has been very good at school and in the after school program.  However, as soon as I pick him up from school, he starts crying and does not stop all night.  He cries about everything!  I thought this was just an adjustment of school, BUT it has been going on for 6 months now.  And just recently he will not spend the night with his grandparents.  He cries for me all night when he does spend the night with them.  My family seems to think he is depressed.  I do not know what to think.  His crying does cause much tension between everyone in my house.  What do I do?  

[bigT907]

I would take your son to a therapist.  Sometimes they can say things to someone else they just wont say to you.  I know that hurts but its true.  My daughter was 6 when diagnosed with ADHD/ depression and anxiety.  I knew the adhd was an issue  that had been obvious.  But the depression was a shock.  I didnt know 6yr olds could be?  Really I figured if you only worried about who was gonna take your crayons (right?)  Turns out she was worried about all kinds of things that were grown up thoughts.  She didnt cry all the time but she would have the "break downs" over really what I figured was nothing and just start bawling... The therapist did wonders!!!