It looks like the crease between my large and small labia split open. not sure what caused it. and my large labia hurts to touch and sometimes it burns when i pee?

The injury you describe is usually the result of coitus without adequate lubrication. A trusted gynecologist can prescribe a topical cream or ointment to provide relief until spontaneous healing occurs, as well as confirm the diagnosis.

You probably have a labia fissure. This can happen with a rough sex. The fissure hurts with urination because urine acts as an irritant. If the fissure is not too deep, it will heal within a week. You can do warm sitz bath 2-3 times a day and no sex until it heals completely. Douching the vagina may exacerbate the problem. If pain gets worse in the next 2 days, you should see your GYN doctor.