Hello there. I am an 18 years old and I've been having these migraine/ pressure like headaches.. I feel like I'm there physically and not mentally. Sometimes I feel as if I'm drifting away. These headaches have been occurring almost everyday for the past month and a half. Some days I get lucky and have a little leisure of not having a headache. I sometimes feel like it's kind of hard to concentrate and see, as if my vision is blurry. I get shaky feelings. I'm not complety sure if it's from my anxiety..
Should I seek medical attention or be worried about a tumor?

It could very well be migraines and a lot can be done about them, but they will want to rule out more serious things, of course. There is no sense in worrying - go to the doctor, get whatever tests. They can eliminate the serious stuff pretty fast usually and that will give you some peace of mind at least. Then they can figure out what's probably triggering what are probably migraine headaches and get you some relief.

This must really have been weighing on you - please don't sit and suffer and worry when there's help available!