My jaw... or something is happening?

okay so for like a month now... i had something happening with my jaw.. i ignored it for a little and i started getting concerned cause i thought i have tmj but i had my tetanus shot before and right now im 14
here's the problem
when i open my mouth really wide there's this uncomfortable feeling in the end of my jaw.. close to left ear
only one side

the other day i had a toothache
im really scared
i heard tmj is deadly
but i dont know if i have it
help!

My jaw... or something is happening?
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