Answer the question about text:

So not good . Two long strides and he caught up with her . He grabbed her hand again , squeezed and gave her a smile . She returned it with a small one , but it soon vanished and she returned to staring into the distance . Back on the TARDIS there 'd been a precious few minutes he 'd been able to talk to her after they 'd saved the Earth . He 'd crushed her into a hug , picking her up off the ground , loving the feel of her in his arms and chiding himself for ever forgetting just how much she seemed to fit there .

What is he starting to realize about the woman whose hand he just grabbed and squeezed ?
He is starting to realize he has romantic feelings for her .