Having a new baby and being.sleep deprived is a really emotional experience. You may well go from feeling ecstatic about your baby to feeling a total failure as a mother, at the drop of a hat. This is normal but.take all the help and support you can find.
New babies may well sleep 20 hours a day, but if it's in 20 min bursts interspersed with screaming that doesn't mean much sleep for you. Again ask explicitly for help and try cosleeping.
Any 'bad' habit a baby gets into can and probably will change within 3 days. Past performance is no guide to future performance, as they say in the finance ads.
Look for breastfeeding and other baby group help before you give birth. Groups run by volunteers tend to be terrible at updating publicity about where and when they meet, and you don't want to find the time has moved to the previous morning when in pain, desperate for bf help and put effort into getting there. Phone all such groups as early as you can in case you need them. Also try helplines and ask for details of local bf consultants or advisers - after getting answerphonrs and being rung back later I found all 4 bf advisers in my borough had moved...
Hopefully you won't need much help but if you do it's helpful to have it lined up, along with where to find a breast pump, etc. Lots of women do find it easy but don't post on these threads! Actually my SIL was helpful telling me she just stuck a tit in her ds's mouth and it just worked, as it stopped me judging myself for having so much trouble (see emotions, above)
Look at Kellymom, especially if medical types are telling you to give up bf when you don't want.