Why am I like this?

I'm not even gonna lie, sometimes I feel like something is really wrong with me. I have been rotting in bed for the past week and more, and I have only left my room a few select times to either have dinner or go out to the market with my mum (happened twice). I never feel the motivation to do anything anymore, and it's gotten to the point that standing up and walking will cause me to lose sense of my surroundings and my vision go all swirly and bright and blurry. Help me. I'm scared.