As everyone's said, do the class, 30 weeks is perfect, and take your partner if you can - it's easier to remember things if two of you have been there. Understanding how breastfeeding works and who to talk to if you have questions or any issues are really crucial. Sadly a lot of people - even health professionals working with mothers and babies sometimes - don't know much about what is actually normal for babies or how breastfeeding works. This can create all sorts of problems.
Otherwise, I'd also have a think about labour/birth/post-natal care and how this might affect initiation of breastfeeding and what you can do to mitigate any issues that arise.
Get along to your ABA group while still pregnant if you can - it will make it easier to reach out later on. Also maybe find out about what services your hospital has - do they have LCs on staff? what are their feeding/baby care policies etc? If they've no IBCLCs, maybe look a few up in your area so you know who to call if you're stuck.
Some discomfort or sensitivity is quite normal in the early days, but pain is a pretty good sign that something is wrong and you need help. That's good to know, also. Don't wait for things to just get better on their own. Ask for help, and ask the ABA or an LC.
All the best