I have a bad toothache and an occasional headache accompanying it. the headache started after i did a new type of meditation which involved heavy breathing. the toothache started a couple of days earlier. can these two be related?

Possibly: Maxillary teeth can sometimes hurt if there is sinus inflammation. But the pain would be transient an of little consequence. There is no need to guess... see a local dentist to have your teeth evaluated to determine if there is a specific issue that needs prompt care.

Possibly: Toothache can cause sinus inflammation which in turn causes headache. Headache most probably, though is from non-related source. Toothache/sinus ache usually from infection which will require treatment to cure, infection is not self limiting. Please see your Dentist before chronic mild pain becomes severe acute pain.