Noah was the same, he was 9 days late and the day he was born he lifted his own head!! Quite an acheivement when his head measurement was so massive!
Tummy time is really important, and mums dont give there babies enough tummy time apparently because they assume its bad for them. But so long as its while they are awake and just short amounts of time during the day its good to start doing asap. Just dont put them to sleep on their fronts.