too much sleep?

My 2 mo old slept almost ten hours last night from 7:30 until 5, fed for 30 minutes then passed out for another 1.5 hours!  At first I was rejoicing, but this morning I'm wondering if he slept too much.  He's acting totally fine and happy.  I'm sure every once in awhile it's ok, but what if this is a regular thing?  This is the second time he's slept like this.  He's a big baby, 13lbs and 24" long and eats fine.  Thoughts?