Can an infected tooth cause headaches ?

Yes if on the same: Side of the toothache.

Yes: It is not uncommon for the pain from a tooth to radiate or be referred to the head and be considered a head ache. Of course not all head aches are tooth probs but if you have a tooth prob you may get a head ache. Obviously you need to go see a dentist to get it taken care of.

Yes: Pain can be referred due to inflammation or infection, and can be interpreted as a headache.

An infected tooth can radiate pain and can cause a headache, or an earache. It will get worse if it is not treated. See a dentist ASAP

All of my colleagues, and I too, agree that an infected tooth can cause headaches, but if not treated, the head and facial pain would likely be the least of your worries, as infections can spread. Be proactive, see your dentist and get this handled ASAP.