What’s wrong with me?

It started on a Friday when I woke up with a bad headache and a temperature i went to school and felt fine until I was sat down in class and felt like I was about to pass out I went really lightheaded and sweaty so I went home and it’s been over a month since that happened i’ve experiences severe brain fog, lightheadedness, fatigue, memory loss, anxiety, small head aches, my eyes hurt when looking at bright things like the sky, and my wars have been ringing ever since that Friday before that day I had a few days off school here and there for similar reasons like lightheadedness etc. I went to the doctors and got diagnosed with low iron and a vitamin d deficiency, I’ve been taking vitamin d and iron pills since then and don’t feel much different I still have severe brain fog and occasionally get dizzy and shortness of breath, has anyone else been through the same thing and could this be something more severe like a brain tumour?