my mouth will only open a little bit and when i try to open it more it feels like there is a block in the way and wont open when i try to get it open further the blocked area [back right side of my jaw ] starts to hurt. what is wrong?
The tempromandibular joints (TMJ) of the jaw are synovial joints that have a small cartilage disc in them, just like in the knee. The disc can get torn and stuck in the joint, causing it to lock (closed or open). This usually doesn't cause pain, expect when the person tries to force it.
Also, pain from inflammation in the joints or from dental pathology can make it uncomfortable to open/close the mouth.
You should probably see your dentist tomorrow for an evaluation. In the meantime, try to stay hydrated by use of a straw. Good luck.