Does TMJ get worse if you chew gum?

Lately my jaw has been locking up on me... I also find, if I chew on something hard or chew gum for a while, I cannot open my mouth until the muscles are relaxed again. I haven't gone to the doctor yet, so I don't know if I have TMJ yet. This has just been going on for a couple of weeks now. I may go to the dentist soon because it is becoming a bother. It's also very painful if I have to yawn, but it's locked up.