Congratulations!! I have a friend who was due the same time as me and she had twin boys. Knowing how much work one is, I have a newfound respect for her and her energy! The good news is they'll keep you busy! Losing the weight was NO problem for her. I know she ended up getting her husband to take every second night feeding. She would pump extra during the day, so he would have bottles for the night. I'm not sure how you feel about formula, but you can always substitute with it on a night feeding when someone else does the feeding. Or, what I did, if I couldn't pump enough was use half breast milk and half formula. They're safe to mix. I don't recommend giving them a bottle within the first two weeks though as they can have nipple confusion. The first 2 weeks will be exhausting, but take all the help you can get!
Breastfeeding can hurt at first. You need to give it a good 2 weeks before your nipples start to adjust. It may be one of the hardest things you do, but believe me it is so worth it! I used to cry sometimes because my nipples were so chaffed and it hurt for my daughter to latch on, but it gets better!!! I don't want to scare you, but I do want you to be prepared! I know a lady who wished someone had told her it got better, because she gave up in the first 2 weeks. Use plenty of lansinoh cream (you can leave it on when nursing, it won't hurt the baby) and get the lansinoh breastpads, they're the best! You can get them with cream in them or without. Also, when you do give them a bottle, try to find one that resembles your nipple the best. Go shopping with the shape of yours in mind and check out all the nipples!
I used the advent portable (not-electric) breast-pump. It took a few days to get used to it, but it works for me and fits in my regular purse for when I'm out and need to use it! My co-worker rented an electric one from the hospital and she says it works okay. However, it takes longer and is MUCH bulkier.
Finally, don't forget to call your lactation consultant at the hospital whenever you have a question! They're very reassuring and are there 24/7 when you need them!
I hope this was somewhat helpful, I know I needed this info when I was pregnant! Good luck and I know you'll be great!