eating less, sleeping more, HELP

[notjusttheirmum]

DD is almost 9 months old
Since birth she has eaten constantly and lots of it. She still wakes at least twice in the night for a bottle.
She has been weened for 5months but these last 2 weeks she is just refusing food. After a couple of spoons she is done where as 2 weeks ago she would eat almost an entire 10month+ jar. She's sleeping more too, 12 hours on a night and between 3-4 hours during the day.
This is so not normal for her and I'm starting to worry.
Is this a sign of teething? She still has no teeth so I don't know if she's just struggling a lot with them?
Any other advice?
If it goes on much longer I am going to the doctor.

[TheHouseOnTheLane]

The thing is, many babies of 9 months are barely eating solids at all and still mainly rely on milk. 4 months was very young to wean....

How much milk is she drinking?

[notjusttheirmum]

at least 630ml a day
I know she was young but it was advised due to how hungry she was