What type of injury am I suffering from?

I just got back from the gym, with a hurt right arm near the rotator cuff, although i'm not sure if its the rotator cuff. I just know it as "the joint that connects my arm to my body."

I did 310 lbs on the squat rack, I must have came down squatting too fast, pushing upwards trying to catch the weight against gravity, and somehow my right arm just gave way and gave an audible crack/pop/not sure what it's called.
It was followed up with this creeping pain that made me feel dizzy, fuzzy, eyes felt like it was sort of on fire. Not quite sure how to explain that.
My arm is still able to rotate around, but in far extended positions away from the body, the pain creeps in again. If I hold my arm out in front of me or away from the side of my body, fully extended it hurts.

Is this a rotator cuff injury? If it is i'll use that sticky I see on the mainpage.

If it is not, I still need to know what the problem could be, I don't want it to be left untreated and weakened.

Go to the doctor. Please, we could hypothesis, but you need to have yourself check, it could very well be a rotator cuff injury, but you physical therapy should be dished out to you from someone qualified who has looked at your shoulder, and MRI's or whatever, and given you treatment specific to you, and your injuries.

Not a bunch of random strangers behind computer terminals.

thehardway is right. If it were a little pain you might be fine laying off for a few weeks but if you heard a popping sound you need to go to a doctor as soon as you can. It sounds like you may have a bad tear, this is something you will need to see a doctor for if you want to keep lifting.