I thought I was feeling ovulation type twinges too, but realized it is actually a little farther south and a bit outside of my ovaries. Then I did a little research and decided it is round ligament pain. I felt it most when standing up quickly and when making quick position changes (right side to left and vice versa) when sleeping.
Any chance this is what you are feeling. Oh, and FYI, I haven't felt it much this week (week 6). Maybe I'm as stretched as I need to be so far (not for good, obvisouly, maybe just done for now???)