I wonder if this just a reaction of the entital start of pumping, and you say that your life hasn't changed but it has... Pumping is a great up hevel, more than it that it seems you realise, not only are you changing and learning a new delivery of your insulin at the very begining, you are working hard to bring it into line, increased testing, greater thought in how your food is reacting, and how to use your pump to counter act all this..
Add to that you probably feel a lot better in many ways as you've obtained more stable control and the body has to get used to this new feeling etc ect..
I didn't suffer from mood swings, but did after the first week, did get a bit tearfull, but this was more relief and joyful tears more than anything.... As I had battle for the best part of 3 years to get the pump, then for first time in a long time felt very well with the very stable levels I had achieved, having the control over my diabetes, no longer having to juggle food to help cover my sensivity to insulin, no longer being enforced to stay up until late at night to have a Levimer Jab having my pump had given me my life and future back...
Hope these moods swings are just you unwittyling coming to terms with the pump, and should subside, it will be worth discussing these with your pump nurse as she may have more experience and insight she gained from other users and might be able to give more practible suggestions