I leave tonight to fly to Dublin. From there I fly to Santiago and then take the bus to Luarca for two weeks on the del Norte. I'm worried about having some first day blues - anxiety about not having much of a plan, guilt about leaving family at home, a general sense of missing home. Anybody have this experience? Any suggestions?
My prayers and Buen Camino go with you
Some of what you've written sounds a bit like separation anxiety, and that is normal. I imagine that you're family is OK with you going and are excited for you. If they weren't, you sound like the kind of man who would see to your family and forego, for the time being, the Camino.
As to feeling a bit anxious about not having an iron-clad plan, you don't need to worry. Such can be an asset, as you have the ability to be flexible and not stressed about missing way-points, or delays, or where to stay and eat... Many start the Camino because they desire to go with the flow of things; other than scheduling their arrival and departure to the Camino, there is little in the way of planning ahead that they do.
Keep in mind that the nature of the Camino provides for easy flexibility in accomplishing your pilgrimage.
My Camino will begin in mid-September, if that is in God's time
But, I think I understand your anxiousness because I felt many of the same emotions that you are having during each of my thru-hikes: five months on the Pacific Crest Trail, and 29 days on the Colorado Trail. I had BIG pre-trip jitters, concerns and anxiousness about missing family.
But within a few days on the trail, those concerns just faded to the back of my mind. I think, given the nature of the Camino, and the easy ability to contact home to verify everything's going OK, you'll be doing great from the very first day. You'll meet new friends, enjoy the sights, sounds and smells of nature and the culture around you, and rapidly gain confidence that you are able to provide for yourself with food and shelter.
Try to remember why you want to do the Camino and focus on those thoughts. Talk to your family about your concern about being gone from them, so that they have a chance to soothe those concerns. And remember that your Camino is only a temporary departure. You WILL be going back home to your family and returning to those things that are of comfort to you in your regular day-to-day life. I would also encourage you to think on how much good and positive that your Camino will bring to you, and how you will return that to your home and daily life when your Camino ends.