Hi, i did my first camino last year without any planning at all. Going unplanned is a great way of exploration and discovery. Though it is with risks.
All l had was a guide book and a overpacked backpack with gear. There will always be room to sleep and food to eat. I never worried about where l would sleep nor how far l would have to walk. I walked what l felt like walking each day and stopped when l wanted too.
I think what you wanted do is great.
it will give you the freedom to do what you want, to walk and stop when you want.
Though the only thing l would recommend is to research any big social events that are happening along the Camino path. Before l started mine, l found out that there was 3 big cycling events during the month of September at different parts of the Camino. during these event's alot of accommodation is booked out. Through luck l only managed to catch the tail end of one of them. I heard from other pilgrims of how they would turn up and find all the accommodation was already booked out.
This is one of the risks of going unplanned.
RECOMMENDATIONS:
1: Do not to book a return flight. Doing so will give you a deadline to meet. You can always find a flight back home (though last minute flights are more costly). But having a flight booked means meeting a deadline, which will put
pressure on you to reach your destination. That is now what you want on your camino.
2. A guide book is a
"guide". It is not "HOW" you must walk the camino, that is up to you. Walk what you feel like, not what the book states you must do every day.
3. Do not make Santiago your destination. Keep walking to Finisterre and then onto Muxia. It is WORTH it since 90% of all pilgrims stop at Santiago. The last 100kms to Santiago is packed, liked a supermarket queue before a long weekend. You will really enjoy the last 100kms to Finisterre and Muxia. (If you can, make the last 2 sections split over 4 days so you have a nice relaxing finish to your Camino. Olveiroa -> Cee ->Finisterre -> Lires -> Muxia. Done like this, it is a nice 15-20kms per day. When you reach Finisterre, swim in the ocean, look for a shell on the beach. Watch the sunset from lighthouse in Finisterre,the beach at Lires and the one at Muxia.
4. Every time you stop for a break, remove your shoes and socks. It will let the heat/sweat escape from your socks and shoes and allow your feet to breath. Remember they are doing all the walking.
5. Every now and then, look back and enjoy the view.
You will get a 90 day Shezgun visa in Europe, don't limit yourself to just 35 days for the camino. It is worth more than that