What have I done to make myself feel like this? – obviously (N)’s reaction was to be really angry and I don’t blame him. Is it yesterday – the tapping or my time with (D) afterwards?

A bit of all three – your mental state is not good at the moment – you are in a transition and anything can throw you off balance.

It’s hard to analyze when he gets angry and I feel really awful. Am I doing anything wrong?

No definitely not, you are on the right road and getting rid of things no longer required in your life. Your only fault is that you didn’t do it earlier and it’s all coming at once for you and not easy to deal with.

It’s like you have balls coming to you from different directions.
A Spring Clean!