Re: Back from dentist, would like to cry now..
A night guard can help with some TMJ cases. Lots of times TMJ issues can be a result of clinching, which causes muscle spasms which can lead to headaches-including migraines, neck pain, facial pain, etc. A properly constructed night guard, can help break this muscle spasms cycling. The night guard is not an instant cure, but being diligent about wearing it should make a difference.
In the States, one typically needs a referral from your dentist to see some dental specialist. Not sure how that works in Canada.
Regarding the lump, that sounds more medical.