From what you’ve described, I’d say that the headache is NOT from a hangover. Still, your body might react differently. I don’t like beer, so I seldom drink any. When I do, I get a quick rush from it & I tend to feel bad while coming off the rush. Still, it is nothing like the hangover I get when drinking too much liquor.
Before drinking beer, you might try eating some bread or mashed potatoes before you start drinking. This will help to absorb some of the alcohol instead of it going straight into your system. After drinking, you probably should greatly increase your water intake as alcohol does dehydrate your system & the water offsets that dehydration!!! I used to have a drinking buddy whose cure for a hangover was to drink 1 glass of water after EVERY alcoholic drink that she consumed. She swore by it, but I never tried it. You might want to try it to see IF it could help you.
Do some research on hangovers & see what other remedies might work best with your particular body. Just because it works for me & many others who drink, it doesn’t mean that it will be the perfect cure for you!!! On the other hand, just because it doesn’t work for me & many other drinkers, it doesn’t necessarily mean that it won’t help you. Pay attention to your own body & you will be able to learn what it is that you need!!!