Toddler head injury

I asked my toddler to quickly tidy her blocks at Grandma's before we left. She came in a minute later a bit tearful and tired. I put her in the car seat and she was repeating sorry and ow. She then fell asleep immediately. This was at 5 and she has pretty much been asleep since. She screams if I move even an inch away from her. I've given her calpol, an hour after her temp was 38. She's tried to sit up a few times but appears very confused and will lie back on me. She's said mummy, her siblings names even though they weren't there and Grandma when my mum came in the room but hasn't been able to say anything else. Im assuming she hit her head when she stood up as the blocks were under a table. At what point would you seek medical assistance? She's acting very out of character, she's never been a clingy child and will always bounce straight back up from a fall. Hasn't wanted food either. Just not sure if there's anything out of hours could do and don't want to drag her out if its not needed as she would be hysterical if not on my lap