What Causes Dizziness And Headaches Radiating From The Base Of The Neck?

Hi I m a 19 yr old female. I have a history of bad headaches. But now I m suffering from headaches mostly/almost exclusively/but my entirely- when lying down..starting at the very base of my skull/right side and seems to be pushing through my forehead just above my right eye. I also get this intense pressure in my head , also starting at the right base of my skull, like its about to explode then finally releases. Resently I ve been seeing stars in my vision as well, even at night. And also dizziness, like I ll feel fine one second and the next I m catching myself falling..but I ve never actually fallen all the way..more just lose my balance but it feels like I m passing out for a very brief moment. I ve suffered from migraines my whole life but this feels different somehow. Is this cause for concern or just a new migraine attack?