Killer headache- any ideas on causes or remedy?

[LuckyLopez]

The back/ top of my head has been hurting all day. It's worse when I bend down or move my head too quickly. I've just taken some paracetamol plus and ibuprofen 400mg but it's yet to kick in. What the hell is it? Any likely causes? It's much worse than a usual regular headache.

Are you dehydrated? Try drinking some water.

Or you might be coming down with a cold. I often get a killer headache as the first sign.

Could be both I reckon. I am terrible at not drinking enough.

This just seems so severe for such a little reason as water