Marcia , you had an unfortunate experience and were not the only one.
Sometimes there are genuine mistakes (mostly walking sticks), but there is potential petty theft along the road.
One shouldn't see a potential thief in every stranger (or peregrino), but on the other hand it's better to be safe than sorry.
Always watch your belongings and/or keep them in safe custody (which may be in lockers or watched by a friend or acquaintance). Keep important documents (passport, wallet, credit cards, etc.) at all times in a "marsupio" (did I hear "fanny-bag ?) under your undivided control. At night time you can attach it to most bed posts and keep it under your pillow. Don't forget it on a bathroom hook after showering
Keep a scanned copy of your passport and/or identity cards in another compartment of your backpack, as well as an
e-mail attachment which you should have sent to yourself.
Said all that, be careful, enjoy your walk and Ultreya!