When dd was 2 weeks old, I only left the house with her when I was with dp who was on paternity leave. And that was him driving us to essential things like dd needing to get checked over and registering her birth. We went out for a walk to the park once and I could barely walk, I was still injured from the birth. When dp was back at work I think it was quite a while before I dared to go out. I was scared of her crying, scared of breastfeeding her outdoors, still in pain, scared of bothering people, just like you.
You've just had a baby and your hormones are probably all over the place. Give yourself a break. Don't lock yourself away but don't feel obliged to go out. She's 2 weeks old that's nothing. I don't think it'd fully sunk in that I had a baby by then. I spent all my time watching dvds and breastfeeding.
When you're up to it, start with small trips to local shops or parks. Take your baby to get weighed. If you have a partner/mother/friend/other family member who can come with you a few times that might help you build confidence. Don't worry if not, you've already been out on your own, you're already way ahead of where I was! You can travel further for longer as she gets bigger and you get more confident - which you will. Remember in these early days getting out is more for your benefit, as I said before don't feel obliged. I used to feel guilty for not taking dd out but I look back and see that was silly. She loves running around outside now she's 15 months but at 2 weeks she didn't know she was born, literally.
And don't worry about other people. Trust me most people love to see babies, especially really young ones, most people have been there themselves with a newborn and know what it's like. They'll either smile or say awww what a gorgegous baby, or they'll ignore you.
Speak to your health visitor if your nerves and anxiety does not get any better but honestly you sound completely normal. Most new mothers feel like this to start. Most people have no idea I felt that way apart from my dp, just because another mum might look confident and together etc doesn't mean she is. Congrats on your baby op! Enjoy these days, I really miss the days when my dd would stay cuddled into me on my lap for hours. Once they start crawling, it's game over! My dd has colic too, it doesn't work for everyone but infacol was great for her. X