I have recently been getting some very bad headaches, as well as being lightheaded. What could be the cause?

ANYTHING... this could be as simple as being over tired or it could be all the way up to a tumor... there is no way for us to diagnose this over the internet. You will need to see a doctor if you are concerned.

ANYTHING....this could be as simple as being over tired or it could be all the way up to a tumor....there is no way for us to diagnose this over the internet. You will need to see a doctor if you are concerned.

Thank you, I may have to. It just recently started and has been going on for a few days now. I haven't thought much about it because I get lightheaded every once in a while but it has never lasted more than an hour or so. This has been continuous for at least 3 days and counting.

Could be a hundred different things but that is serious enough I would book a quick trip to the doctors.

The most common ordinary cause is dehydration.
Don't waste a trip to a doctor until you have had plenty of fluids for several hours.