Reality check:
If a person has been in a coma for nine months and hasn't moved for a long time, their muscles would have greatly atrophied (shrunk), some joints would have gotten a contracture (that is when someone is immobilised for a long time (period of weeks to months) and the joints become so stiff that they can't be moved, and because of the shrinking muscles, the joints get stuck in a (usually bent) position and can't be stretched or straightened out unless someone has been helping her move every single joint every few hours every day) and they would have gotten pressure sores unless they have a pressure care mattress and someone who repositions them at least every 3-4 hours minimum.
In short, the girl would not have been able to get out of bed, but would have been able to make herself fall out of bed. She definitely wouldn't have been able to walk straight away - at least not without at least a few weeks to months of rehab.
But... I know this is a story and most people don't know what it's like being stuck in a bed for so long (it's painful, frustrating and difficult). So... I will suspend my understanding of reality to see what you write next.
taetaebootae