Morphine and pethidine are similar in their effects. They are both opiates, and both are likely to make you feel drunk/stoned. The hospital will likely have their own policy on which one they offer to labouring women.

If you are put on a drip to strengthen contractions then you can still use movement to help you deal with the contractions. So make the most of the birth ball, or moving around the bed. Also think about taking a tens machine with you, as well as the heat packs and massage techniques you probably have already thought of. An induced labour does not mean the natural coping methods are unusable, although you may need to concentrate more on staying calm and relaxed as the contractions will have a bit more punch.

Best of luck for tomorrow