I just have no clue about mattresses. We have an oldish memory foam one that has been OK, but now gone very squashy and is really uncomfortable now I'm pg. I slept on a much firmer sofabed-style one on holiday which wasn't a quality one at all, but felt much better.
Can you recommend me one or a place to get good advice/try them out? Also I don't want to spend loads - some people seem to think it's mad not to spend thousands on the best possible, but that can't be right?