What else can I do?

[JustEllie]

My baby is 10 weeks old and has a horribly flat head. Obviously, as first time mum I'm panicking more than I should. She is a good sleeper- during the day she naps a lot and sleeps almost (wakes up once) all night through. HV said to reposition her head and have some tummy time. I can't hold her all day long and she doesn't like it for longer time.

What else can I do?

I think you can get a mattress which is supposed to help OP.

Have you tried her in a sling too?

When we noticed the flat head, we started carrying her in sling and reduce the time when she is lying. hope soon we will see if theres any impovement