Why do I get a bad headache/migraine while I drink?

I eat plenty beforehand. I drink lots of water in between drinks. Yet I get migraines/headaches WHILE I drink.

One theory I had was that I already went to the functions with a migraine that had started to form. This was for two instances I got a bad headache during drinking.

As for the last time I will be honest, I had little water and basically ate nothing. So I feel like that might have been the cause.

If this is just an issue of hydration and eating in order to not get a migraine while drinking, I can solve it. But, what could be other reasons for this? And what could be the ways to solve them? I should also note I have only recently started even going to parties and drinking, so I have basically 0 tolerance.