Headaches, blurry vision, blackouts?

[mezzopiano]

just recently ive started having headaches and my left side has recently started to go numb from time to time. ive had temporary blackouts (everything suddenly goes black and then i twitch back into consciousness) and seizures in my legs for several months but i didnt think it was anything serious.
i visited a local doctor a couple of days ago when i started getting the headaches because they were accompanied with fatigue, blurry vision and numbness/loss of sensation on my left side. the doctor performed a basic neurological test with a rubber hammer, getting me to follow his finger with my eyes etc, and insisted it wasnt a stroke or anything. he prescribed me some ibuprofen and said the headache should go away in a few days along with the symptoms.

its been two days and the headaches have only gotten progressively worse, and my vision gets worse everyday. my symptoms are very similar to those of a brain tumor and its really stressing me out. cancer runs in my family (my great grandmother died of cancer), and i would really appreciate an educated opinion about what this could be.
i have another appointment with the doctor tomorrow because the ibuprofen has had no effect. should i ask for an MRI appointment, or should i just trust the doctors opinion?

please help, this is really stressing me out.