I get what your Mum is saying about the good pain. It's not so much that it's a 'good' pain, but more like it's a constructive pain - you know that you are working for something at the end of it. It is hard to know how anyone will deal with labour and contractions as I know women who think they could but really struggled to stay focused and others who thought they wouldn't be able to deal with it do super well. IF you think that you will struggle, it would be well worth looking into doing a calmbirth or hynobirthing class as it will teach you how to focus through the contractions and manage the 'pain' of them more effectively. That's not to say at some stage you wont feel like you need pain relief, but if you can use calmbirthing or hypnobirthing tools to get you most, if not all of the way through that's great, because you really don't want to be turning up at 4cm dilated and screaming for an epidural kwim?

ETA - it might also be worth looking into getting a Doula to help support you through the birth too.