What is a migraine?

Honestly I never know if this feeling I feel is a migraine. I get a few a year. The feeling is like a headache but more intense. Almost throbbing. I get nauseous. I try to take Tylenol and eat something but it doesn’t seem to go away. It’s like I almost need to stop what I’m doing to close my eyes or lay down. But it hits me when I’m working. I’m looking up some medications I can keep in my pocket for when I’m experiencing these headaches. Maybe some candies in my pocket. I heard chewing can help? Sometimes I feel a little better when I drink some sprite or ginger ale, but again it’s like the Tylenol. It doesn’t go away so easily but it gives me something to take my mind off?