You say you're 16 - you can get a GP appointment yourself, show her you want to make steps to get well again.

If you're in the UK there are services you can self-refer to as well. The wait lists tend to be long, but it will hopefully show that progress can be made.

You could also try some techniques at home - with my students we recommend Healthy Minds (https://www.lpft.nhs.uk/young-people/lincolnshire/young-people/i-need-more-help/low-mood-and-depression) BUT this would be temporary until you could get further support

On that, you could talk to teachers at school, school nurse - anyone in a position with safeguarding will have a requirement to move things forward and be able to give you more specific advice