http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Eyes_-_uveitis_and_iritis
Uveitis means inflammation of the middle coat of the eye, which extends from the iris at the front of the eye to the retina and choroid at the back of the eye.
Iritis is inflammation of the iris, the coloured part of the eye. It is a form of uveitis and is more correctly called anterior uveitis. The cause is unknown in about 40 per cent of cases, but may include infections, autoimmune disorders, arthritis and skin disease.
Iritis symptoms typically begin suddenly and can include a red eye, eye pain, light sensitivity, blurred vision and a small or distorted pupil. Attacks typically only involve one eye at a time. Without correct treatment, iritis can cause permanent visual problems. Young and middle-aged people are most commonly affected.
There is no cure, but treatment of individual episodes can control inflammation and prevent complications. However, iritis often comes back.
Don’t worry but it’s apparently uncommon for the eye to explode, though worth treating. Of course it could be something else.