1) Congratulations on your new baby!
2) It is very overwhelming the first few weeks. Hang in there and go easy on yourself. You're doing great. If you want to go out, can you take your baby with you? The carry great in a sling or a wrap and if you practice at home where you are comfortable, you can nurse without it being a big deal.
3) If your nipple are really sore, it is worth talking to someone who knows about breastfeeding about the latch (attachment) just to make sure that baby isn't on your breast in a way that is causing it to hurt more. There are some great pictures here http://www.kellymom.com/bf/start/bas...resources.html
4) Ignore the old health vistor when it comes to feeding info - she's obviously full of bad advice. Give NCT or LLL a call when you have questions - they are kind and warm and helpful.
5) You can do this. I know it seems like an eternity of nipple pain right now, but it will get easier. By nursing your baby you are avoiding all the risks of formula feeding. You baby gets perfect nutrition, plus immune boosting, brain building, and cognitive and emotional development each time you feed her.
You're awesome, you're strong and you can do this!
Pop back here as often as you need for advice, support and encouragement!
And if you have specific questions be sure to ask them. The moms here have tons of exellent info to share.