Is the pressure in my head and behind my eyes a result of the overexposure to the heat and sun?

I've worked outdoors for years in Georgia and about a month ago, after a couple cups of coffee, i gradually became dizzy and this lasted for the next day or so. During that time i stayed indoors, in the dark mostly, drank lots of water, and by noon the next day the feeling went away. I should mention that i drink a good bit of beer daily (6 or more). A few days later on vacation, all the while drinking beer with my family, i decided to have some coffee one morning. And very quickly, this disoriented feeling came back and despite my efforts to rehydrate with water and gatorade i spend the next few days in a haze. I laid off the alchohol for a couple days. After i return to work i noticed these symptoms came on the strongest when i was in the sun for a certain amount of time. I go see the doctor and tell him all about the last several days, including the alchohol. He thought it was possible i was detoxing and suffering withdrawls and prescribed Paxil to deal with the anxiety of withdrawl. I've had bad experiences with that and wasn't and still not experiencing anxiety, so i didn't take it. Also, my blood pressure was a little high and this concerned him. I was hoping i was going to get something to make this woozyness and pressure in my face go away, but no luck. So my wife and i are looking for things to eliminate this feeling, anything from detox teas, multivitamins ( a lot minerals in the ones i take are said to attribute to high blood pressure reduction), relaxant teas, etc. There are certain vitamins and minerals such as niacin, potium, calcium, riboflavin, magnesium,B6 and B12 that all help reduce blood pressure. However, the daily value in most of these are at %100 or higher in the multivitamins i'm currently taking. I've read that to treat some cases of high blood pressure, these particular vitamins and minerals have to exceed levels that meet the daily value in order for it to be affective against it. And the times when i've experienced the strongest pressure behind my eyes and woozyness is after i've been in the heat for a certain amount of time. Also, when i get frustrated or stressed out and get myself worked up, this feeling comes on strong. My eyes get real sensitive to light. I'm currently not drinking coffee at all. I went a couple weeks without beer and noticed this feeling less and less during that time, but very slowly. I don't know if it's the sun or high blood pressure or both, and if it IS the sun and the heat, what do i do to alleviate these symptoms for good?