Can you post what your day currently looks like, so that we can help you have a look at your routine.
At this age their A time is very minimal, and basically incude a feed, nappy change, quick cuddle and back down for a nap. Most lo's this age only do A time of around 45 mins to maximum.
A lot of lo's at this age have a very strong sucking reflex, so if your lo needs the extra sucking, I can't see a problem in introducing a pacci for sleep, as long as your lo does not become dependant on it.