Thanks for the advice and I'm definitely starting to ignore him a bit more when he plays up. I'm trying to get my OH to stop responding too. I'm doing my best to just enjoy my son, which I do most of the time anyway. With 9 days till due date I'm aware that all to soon we'll both be without our time together.
For the past couple of days he has calmed down somewhat and the threat of naughty corner has been enough for him to do as he's told. I've worked on myself too - inwardly counting to three myself and picking my battles more carefully and giving him plenty more positives than negatives.
I'm so proud of him in so many ways and just don't like getting angry with him. I had PND for the first year of his life as he was such a difficult baby, he had colic, didn't settle for sleep, he hated baths and car journeys, wouldn't be apart from me for more than a second. We struggled basically and I lost out on a year of loving and enjoying him - I don't want to go back to that, I want to savour every moment. I feel we have come so far since those awful days that I don't want to be getting stressed over Terrible Twos, I need to learn how to deal with the tantrums and to continue to enjoy my son, because he is so fab in so many ways.