I'm sorry your experience was unpleasant.

Sometimes a doctor will ask for this permission, BUT you don't have to consent and he still has to treat you. I wouldn't agree to this. Did you sign it?
I also think he seemed insensitive by referring to your dissociation as an 'alien experience'. I guess even though some doctors are smart it doesn't always make them sensitve to others needs.
Yes it is important for all women to get regular gynecology examinations even if they're not sexually active. It's unfortunate you weren't told that when you were growing up but that's not your fault. I hope they fixed your problem - it sounds like some of your internal areas ended up through gravity, falling out and this happens sometimes. Hey we're all different and not everyone knows the perfect rules in life, so don't feel shame.
Maybe after you're completely healed, you can look for a female gynocologist and explain your circumstances - hopefully she would be more sensitive. Don't let this discourage you from getting regular exams in the future.