DD is 7 weeks, breastfed (not sure if that's relevant).
Sometimes while I'm feeding her she acts really strangely. I can only describe it as being overexcited. She thrashes her arms and legs about, shakes her head all over the place while trying to latch on, has a manic look in her eyes, and growls a lot. She sucks for a few seconds, falls asleep for a few seconds, then wakes up and becomes all hyperactive again. This might continue for an hour or two, until she's eventually had enough milk to relax and go to sleep properly.
My theory is that she's overtired, since she keeps falling asleep, and we all get a bit cranky when we're tired. But it could be something else entirely.
I am a first time mum so I'm wondering how normal this is and what to do about it? She behaves normally for most of the day and we don't usually have an issue during feeds.