1)
It is far better to be on your own than with someone just for the sake of not being alone. That applies to friendships as wells as relationships.

2)
To proclaim my understanding and competence on a subject, and then change my mind on it because my understanding was shown to be incorrect, it’s embarrassing for me, especially in public, as I fear it makes me look stupid. I prefer to avoid this and usually wait until I am sure of my understanding and knowledge before I start talking about it.

Agree.

3)
I am naturally sceptical of second-hand information and whenever possible prefer to trust my own experience to reach a conclusion about something.

Depends on the subject and the source of info. Both options for number 3 make sense, but I'm leaning more towards the first (bolded) one.

4)
If I need to learn something quickly, my first instinct is to ask someone I see as knowledgeable on the subject, rather than find my own way through it in books, the net, etc.

I don't know many people who have info I would require. Both "instincts" (asking someone or independent study) are applicable. For instance, if my Jeep has a mechanical problem, I'd either call a few nearby car shops and/or my mom's mechanic boyfriend for input.

If I needed to learn something more abstract or theoretical, like a political solution/alternative or info on how to write scripts (for my amatuer fan fiction), my "first instinct" would then be to look for "how to" books and internet websites.

5)
I have a very good idea about my level of sexual attractiveness (or lack thereof) in relation to others around me.

No idea how my "looks" are perceived by others, in terms of "sexual attractiveness." Unless they tell me.

6)
Especially in moments of crisis, I am inclined to be paralyzed by indecision and tend to wish, later, that I had acted more quickly.

7)
I worry far more about appearing stupid and/or ignorant among others than I worry about being awkward when dealing with people.

8)
On the contrary, I usually tend to think I am already doing, or have already done, enough anyway – unless it is something that depends on a very specific standard that has to be met, in which case I meet it.

9)
Sometimes I may even wish I was better in such things, but normally I think that those who take physical risks (or risk getting into physical confrontations) easily are just being silly.

10)
Poetry may be nice and all, but it’s ultimately pointless – I prefer writings that actually communicate something in a more straightforward language.