any insight to his behavior?

Anybody have any insight to this behavior? Last night we had MC, I arranged for my oldest son ( who is with his father, my xH this week, we trade off with my son weekly ) to babysit for my partner and I's two year old so we could attend our apt. So after work I picked up my son brought him to my house and rushed off to the counselor. After our apt. my partner now had to rush off to his Krav class. So I got home fed our new baby then packed up the kids in the car so I could take my son back to his fathers house. While I was dropping him off, my xH new wife came out and we chatted outside of my car for about 15 min or so. When I went to leave I saw I had missed 5 calls from my partner. When I called him he was angry with me. He says he was upset for the following. 1. I didn't answer when he called 5 times 2. That he got home and was worried why I had taken all the kids and left the house 3. I didn't tell him that I was driving my son back to his fathers after babysitting for us (I did tell him the previous day but he must have forgot ) 4. That he doesn't want his children around my xH or his wife and 5. I said I was going to cook dinner after our MC apt. and I hadn't. None of his reasons seem like real issues to me… AND the reason this is so strange is in the past I have gotten upset with my partner for not answering my calls when I was worried about him. We have had several arguements about this because according to him, me getting upset with him for not answering is stupid, I should realize he is just unable to answer sometimes and it makes him angry when I would do it. So I don't do it anymore and haven't for a year or so. Also, my partner has never done this to me. In fact truthfully in the past I could leave for an entire day without telling him where I am going and he wouldn't call me even once to see where I am or what I am doing. So I wonder, why this behavior / reaction from him now? Any one have any insight as to why he might do this now? Of course I was hurt that he would be angry with me when I felt like I hadn't done anything wrong. Instead of arguing I just apologized and dropped it but I am still baffled by his behavior…

Put the internet to work for you. via Personal Recipe 2629979