Has anyone else had trouble fitting a newborn into a Pebble?

[Rooneyisalwaysmoaning]

I'm wondering if it's just me and something I'm doing wrong.
He was 7lb at birth and when we put him in the seat, he was sort of too small - it looked like he would just slide out if there was an accident as the straps were too high/too low/ too far apart iyswim, he was just above the crotch strap and his legs were together above it. Not one either side.

Is this a normal issue? He is now 6 weeks and it's a better fit but it really concerns me that he was potentially unsafe for weeks.

Yes, not sure about the head support? Is that the circular thing with the hole in the centre? The straps are on the lowest setting and the wedge is the right way round too.

Thanks. We have the easybase 2, as our car doesn't have isofix. That's a good fit - it's just he looked all wrong in the seat, Dorel have asked me to send in pictures and they'll see what they think.